I'm not real sure why you went to a rear sump pan to start with. I've always ran the stock front sump pan, pump, and pickup on my '67 327; and I've never had any oil related problems.

I'm curious if you are running headers, and if so, how do you get your oil filter on and off? The stock front sump pan has a recess specifically designed just for oil filter access, which is tight with stock manifolds and pipes. It really gets close with headers, especially Hookers. I always wind up forcing the filter between the pan and the header tubes, it never goes on or comes off easy. Seems to me like access would be impossible with a rear sump pan.

I'd agree with the others that you've probably wiped the bearings in your engine. When you don't see pressure at the guage withing 15 sec. or so after starting, SHUT IT DOWN, and don't turn it over again until you're sure your going to get oil to the bearings. A used engine can run a few minutes (I've heard of one going for 15 minutes+, but I wouldn't want to own it) without oil pressure without ruining it; but a newly built one doesn't have that luxury.

And finally, as for the intermediate pump shaft in a Chevy II V8 being a different length that other smallblocks; I don't think it is, but then again I've never laid it out beside another one, so it could be. I just don't have a definitive answer for that one.

Randy