i am gathering parts for a 31 buick 3w coupe project and have found a '67 430 buick engine. i really want to put a nailhead engine in it. my questions are; Will the nailhead bolt up to the 67 400 tranny? are the flex plates the same? how close would the motor mounts be? does any body have a measurement from the back of the block to the center of the motor mount? how much bigger is the 430?