Getting ready to swap a 5.7 into my 73 Dart Swinger

I finally see why everyone's so wound up about motor mounts, TTI, spools, steering box... My spooles were pretty shot. Not surprising as the entire bottom looked like they used the car as a stump-jumper. 1 MM was fairly cracked and the other was welded at the factory, late on a Friday before a holiday with a hangover. I just wacked em both out. Put my MM where I wanted them. Y'all got some real battles going on :)
Yeah thanks for rubbing it in I was picking up a lot of momentum and now I'm stuck scratching a hole in my head I am considering going with a manual box just to get this done I'm so tired of working on this car and not driving it also the only material I seem to be able to find is 1 1/2 stainless steel or 2 in any input on what you guys think about 1 + 1/2 piping for the headers I see the main size that companies advertise is 1 5/8 + 1 3/ 4