I am finishing up my restoration of my '69 and trying to put a mechanical fuel pump on my 383 crate motor. Both of the pumps that I have tried (Holley and Summit) run into interference with the input almost hitting the frame (or if I take the pump apart and rotate the assembly, the output almost hits the block). I have the engine mounted on normal motor mounts so the only thing I can think of is that the new Chevy blocks are made differently so the the fuel pump sticks out more. If I could get just a little more room than these pumps offer, I could probably safely get lines on it. But it seems that almost all brands of these 3/8 inch I/O pumps offer the same configuration of input/output, side-by-side with a pretty big gap in between and the input sitting very deep on the pump. Ive seen 1/4 inch pumps where the input/output were at the same level and that would be perfect if I could find that in a 3/8 inch model. I really want to stay with a high performance mechanical pump - going electric would be a last resort. Does anyone know of a fuel pump that might work for me?