HI everyone, I have a story i like to tell you guys about when i put my 400 in my chevyll. Back in 1991 i bought my 67 chevyll with no motor or trans ,but did come with the stock front sump pan,oil pump, pickup tube. At this time the only motor i had was 68 307ci , put the oil pump, pickup,pan on and put in with no problems. About a year later i found a 400, i put the pump in on problem, put the pickup in and there was no place to mount it,the bracket was lined up with a main cap , so we drilled and taped the main bearing cap and mounted it with a small bolt,that seamed to work out ok, so next we were ready to put the pan on and my brother said wait lets turn it to make shore everything is ok, we turned it and it locked up After about ten min we found the problem a rod bolt was hiting oil pump so we took out pump and took it to the bench grinder and took it down just so the bolt would pass it,the whole side of the pump. Hope this helps someone .