Something doesn't sound right. Somehow water got in the engine. For that much rust had to have been exposed to high humidity or water. I have bare blocks that have been in my garage for 25 plus years only very light rust on cylinder bores.

Where is the crack.   

This is the car that sold for 267k? The 66 R code?

OK, I might have been thinking about the 66 that just sold on BAT.
10/4 on everything, looks like a plug in the rear of the housing so probably correct, ignition?
I do believe the sidewinder is correct though for a 67 W code.

https://bringatrailer.com/listing/1967-ford-fairlane-33/?utm_source=dm&utm_medium=email&utm_campaign=2024-03-20

X2

I thought that if the adjuster was all the way down that would put a lot more stress on the system? From what I described would it be worth measuring for new push
rods to place the adjusting nut all the way up as far as possible? I notice and read guys building engines talk about .010" difference in push rod length. On my engine I would be talking about at least 1/4".
Yes, proper Ford C4AE stands are being used. There are no end support stands available other than the DOVE units which would involve taking head bolts out which since the engine has been together for decades, I'm not going to get into that. The engine is sealed. I have been asking for someone make a Billett Steel simple slide on end support stand but no one wants to make it for the High Riser.

I probably have a dozen spacers or more (been picking them at swap meets). If I measure and fit according to specifications, then install and spin the crank and everything feels smooth, would that be satisfactory? If rotational torque is within spec.?