OK, with your kind replies and much investigation and removing the engine finally, again, I think I found the problem. I mean it could only really be 3 things:
All seem unlikely to have anything wrong with them to let the oil hole/notch out of the bore slightly and jet oil out. Which was happening. This is how I noticed that problem. I let the engine warm up till the oil was hot and thin, then I quickly shut it down and removed the rockers and the dizzy. I manually primed the hot thin oil through the engine. Aside from the gluttony of oil still pouring out the roller tips on the rockers I noticed oil jetting up along sides of some of the pushrods from the galley.
Shinning a light I down there I could see oil jetting out the sides of the lifters that were at lift. There was a small emulsion of oil around the lifters not at full lift but nothing I would deem not normal, if that makes any sense.
Using the starter to bump the engine with the manual prime running the oil jetting out the side was consistent with any lifter at the full lift position.
That's one problem. Another still way too much oil coming up through the pushrods when hot. Just with manual prime and the engine motionless there is oil pouring out the roller tips of the rockers and this is strictly push rod oiling.
First things first. The mechanical fitment of the roller lifters. So this has driven me absolutely batty until now, at least I hope. Because the problem is with the block.
This is the engine as of today. I totally forgot that I had already exchanged the Comp lifters for another set of Comp lifters a year ago. It's hell getting old. It came flooding back when I popped off the intake and it didn't look like this.
I guess back then I thought I had caught the problem of the machined lands sticking too high in the bore. Comp Cams told me that this set was an old design and so I traded for the newer design (pic above) where they lowered the upper machined land so more of it sticks in the bore. However I still missed the fact that the oil hole and notch are still rising slightly above bore.
Here's the oil hole and surrounding notch on the side, which according to the article so generously posted by 1964Fastback this is the incorrect oil hole location as these let too much oil to the head via push rod oiling, which I can attest to when the oil is hot and thin.
But I digress. Here's the apparent problem.
The actual lifter bore doesn't actually start till further down the apparent lifter bore. If the bore went nearly to the top the oil hole and notch would be covered.
So this is a 1966 "Y" code 390 block. It just so happens I have 3 other FE blocks in the garage to compare. 2 of which are also 1966's.
Here's a 1966 352 fresh from the machine shop
Its lifter bores go to the top with just a chamfer.
Here's a 1966 crusty "Y" code 390 block.
It too has a lifter bore all the way to the top with just a chamfer, so these lifter and cam will work in these blocks, just not the one that it's intended for.
However thanks to blykins and his generous measurements of the Morel lifter I think that will work as the distance from the Comp Cams lifter wheel to top of the oil notch is 1.68 and the Morel is 1.5 that lowers the oil hole 0.18" enough to be covered in the weirdly machined lifter block.
That should solve the mechanical fit problem and a good portion of the oil control problem. Now according to the article about oil hole location, the Morel's are in the proper position (This is all new to me) and if correct should do a much better job at metering oil to the rockers and that might just solve all the oil control problems.
If still too much oil is going to the roller rockers then I'll have to have solid push rods made and go back to a precise metering of the pressure feed port in the head.
As a side note before I removed the heads and intake once the engine was back out of the car, I decided to do another static compression check of both heads and better listen for leaking valves.
Glad I did, #8 is also leaking through the intake valve and quite a few have very slight leaks on the exhaust valves. So that's 3 intake valves leaking, no wonder why the vacuum gauge was bouncing like mad all over the place at idle. Good grief now I have to send both brand new heads back to Edelbrock to have them fix their initial valve job.
I swear this engine is jinxed.
I do wish to thank you all very kindly for your input, it's been invaluable.