So here's what happened...

I put the valve covers back on and warmed up the engine until it started ticking again.  Then I added another quart of the same oil that was in it.  The oil in the engine had about 500 miles on it.  I had put in 5 quarts with the filter.  This is a Canton "T" pan, but not the race version.  The oil is the white label Castrol GTX 10W30, not synthetic silver, or synthetic blend green.  With the engine running and ticking I added one quart from the same batch I bought when I changed the oil in the car.  The ticking got quieter.  I continued running the car for a while just in case it took some time to heat the quart I added back up to the point that it would start ticking again.  After about 10 minutes of running and revving the engine to get it to heat up, the ticking never returned.

Then I jacked up the car and drained the oil.  I did collect a sample of the oil for analysis.

Straub had recommended a full synthetic 10W40 oil, which was surprisingly difficult to find.  Eventually I found Royal Purple HPS (high performance street) full synthetic 10W40 at the local NAPA auto parts (they also had Amsoil, but that cost almost double what I paid for this purple stuff, $14/bottle) I got 6 quarts and a NAPA gold filter.  I changed the oil and put in all 6 quarts (not 5 like the last oil change).  It was even quieter than it had been before the oil change and no ticking.  I ran it for a while and still no ticking.  Then I took it out on the road and on the highway to get fully hot and it hasn't started ticking.

So now some new theories:

- 5 quarts isn't enough oil for this engine.  It never lost oil pressure with 5 quarts, even on the road accelerating and turning corners, maybe it was sucking a little bit of air and foaming the oil, but I never saw any evidence of that
- Perhaps this oil had been damaged by fuel contamination and adding a fresh quart helped it a bit.  It is a carbureted car with a choke and it runs a bit rich sometime, but I'm surprised if the oil could be fouled in 500 miles, perhaps it is marginal for this application and just a bit of wear and the oil viscosity gets too low for these lifters.
- Maybe this oil formulation and grade just doesn't work well with these lifters.  I've always kind of assumed oil was oil.  I pay attention to weight and I know synthetic has better temperature tolerance, but I generally bought what was on sale and since I only drive this car on nice days conventional oil was good enough.  It isn't flat tappet, so I wasn't too worried about zinc.
- Maybe this engine needs the slightly heavier weight 10W40, bearing clearances, or lifter bore clearance might be better served by the 10W40.  I had experimented with 20W50 on this engine and other that burying the needle on the oil pressure gauge, I didn't notice much improvement.  10W40 runs at a higher oil pressure than the 10W30 did, but it is still in the normal range of the gauge.

I'm going to send in this oil for testing, maybe it will give me a clue about what happened.  The good news is it seems to be solved.  Hopefully I don't have to change my oil every 500 miles.

They sent me a follow up email saying 10W40....OK

I had to go to Chicago for work, so I haven't been able to work on this in a while.  Today I started it back up and got it warm enough to start making the noise again.

Then I took both valve covers off and started it back up.  The back three rockers on the driver's side had less oil flow than the front five and the passenger side all rockers looked the same with about the same amount of oil as the front rockers on the driver's side.  So changing the lash didn't help oil flow to the back.  I thought I took a good video of this, but when I went back to watch it, I forgot to hit record.  I did get a good video of the engine warming up when the noise starts to happen.

When I figured out I didn't get a recording with the covers off I restarted the engine, but it must have cooled off a bit because it was now throwing oil everywhere.  The back three on the driver's side still had less flow, but they were flowing as much as the front five were when it was hot.

Should these things be throwing oil all of the time?  When it's hot and making the noise I'm getting a dribble of oil coming out of the roller tip of the rocker arm and a small puddle of oil on the spring retainer.  A small paper dam about an inch higher than the springs mostly contains it.  When the engine was colder there was more oil pooling and it was splashing off the tops of the springs and over the paper dam.

Unless someone has other things for me to try, it seems like I'm going to pull this engine.  Things to check:

1) lifter bores worn / too big
2) Lifters coming out of the bore and unshrouding the oil band
3) Trash or maybe a restrictor in the lifter oil gallery
4) Cracks around the cam tunnel or oil gallery

I don't really have space to pull this engine where I'm at, and we might be moving soon where I would have more space to work so this isn't a project I can start right away.

Also, if anyone has a recommendation for a good FE machine shop in the Oakland - Stockton California area, I'm probably going to need one.

Yes, I used the EIOC method to adjust the preload.

When the lifter was on the base circle, I would adjust the rocker until I felt resistance turning pushrod indicating that I was at zero lash.  From there I turned the adjuster down another 3/4 turn.  Since it was getting noisy when it warmed up, I tried adding another 1/4 turn, and then a second 1/4 turn.  Since those weren't effective I moved on to looking for other problems.

These were Howard's Cams lifters, but they have Morel part numbers on them, so I suspect they were made by Morel.

For what it's worth, I have swapped out the lifters and it didn't change the problem.  The oil is 10W30, Pennzoil I think.  Maybe Castrol.  Ordinary motor oil.

I have a video of this, but it is too big and wrong format to post.

Did you torque the stud itself, into the head 40-45 ft/lbs, or did you torque the nuts to that amount?

The studs were just screwed in finger tight.  The nuts were torqued with the ARP lube that came with the kit.

So I've had a thread insert for a rocker stud pull out of my aluminum head.  It presented itself as an increasingly loud rattling noise.  I'm in the process of figuring out what I'm going to do, but I wanted to ask the community what causes this.  I torqued the studs to 40-45 ft lbs.  I assume if there was a coil bind problem it would have destroyed all the inserts immediately, not slowly over the course of a few hundred miles.  Interested in hearing your thoughts on this.  Hopefully I can fix this and it will stay fixed.