Love the 454 swap I did to the 73, replacing a 325 HP 350. Same mileage, (keep your foot out of it!), pulls a trailer effortlessly, smokes the 33's most excellently, blows stock TH350's though. You will need to really build a TH350, or even a TH400 some. 4l80 is the way I am going, so consider the trans in the swap. If you are nice to the gas peddle, most anything will work just driving around, and when I was younger, I just could not keep my foot out of it. I thought getting older, this would fade....NOT. Welcome!!