The driver side mount does need to be cut per the Schumacher instructions. I went with a 440 Source high volume pump so I had to notch it about as far as I dared and ended up having to elongate the trans cross member holes. The motor and trans sits about 1/8 to mabe 3/16 of an inch forward of its stock location. I'm going to put a torque strap on it because I'm sure the integrity of the mount tower on the K frame has been somewhat compromised do to the cutting. Schumacher, Moparts And 440 Source all have them (I think).
It's true that the 400 is a low compression boat anchor...........BUT...........The car was a low budget build and my boy wanted a big block in his car. Junk yard motor, new cam, used intake and carb for well under a grand. I'm tellin ya that i think it'll go a low to mid 13 and it certainly hazes/broils (dealers choice) the tars at will. It sounds good and most people can't tell its a boat anchor.The car is now a running big block car and in the future as time and funds permit he can stroke or replace the 400.