The oil feed to teh heads needs to be either slotted over - or simply drill a matching hole in the head gasket since the heads are already slotted.  Takes 2 minutes tops.  But you do need to be aware of it.

I have had ZERO problems with cam bearings on these blocks in iron - not sure where that issue came from.  I use a flashlight to ensure alignemnt of the feed hole in the block with the one in the bearing.  The Pond bearings are simply wider, and come from the exact same source manufacturer so press is identical. 

I HAVE had a couple of aluminum blocks - one Genesis and one Pond - where one of the cam bearings walked out from position - didn't spin, just wobbled out.  Easy fix, but problematic.  Turns out that OEMs use a very tight press on production alloy blocks.  Red Loctite is recommended at the very least.

In six or seven years and who knows how many builds I have had exactly one cracked ductile iron main cap.  It was in a +/-700HP drag car and came in for freshening after a few hundred passes with no symptoms at all.  Cap came out in two pieces and we were stunned - the bearing even looked OK.  Split through the threaded "pull hole" in the center of the cap.  An apparent stress fracture at the threads.  Since then the pull holes have been made shallower and/or eliminated.  Probably a non-issue for any new build.

Pressure check time.  I've seen leaks from every possible location.  Easiest way is to fab a piece of aluminum tubing sized to clip the two radiator hoses together.  Have it drilled/tapped for 1/8 NPT and attach a common pump style radiator pressure tester.  Valve covers off and 20 pounds, sharp ears and eyeballs - along with soapy water will usually find it somewhere.  If the leak is too big to hold pressure for long you can cobble up the leakdown tester to deliver a constant moderate pressure so you can continue hunting.

Need a "hot spare"    ?

I dyno'd something pretty close to a basic hopped up 390 a while back.  With a real timid hyd cam, a Performer RPM, and a set of off the shelf Edelbrock heads it made around 352 horsepower - running open through headers on the dyno.  Not bad - but still nothing to get too excited about these days.  No way was it anywhere near the rated numbers with iron exhausts and stock heads.

I've sequenced a couple of them, but I have used a crank trigger.  The distributor is used only for the cam signal - I do that by breaking off all but one of the reluctor "teeth".  I also had a problem with a FAST distributor - lost one on the dyno - and after the replacement subsequently failed the customer on the road he gave up on it and went MSD/batch.

Have you given any thought to milling windows between each main web and wrapping the pan around the side of the block so that the kickout is effective as it is on a non Y block application?

Probably should not have mentioned that one......