1974 360 horsepower rating
Running 3 inch exhaust really helped pick up on the low end IMO, as for the heads, they were stock smogger era, nothing special done to them beyond a basic 3 angle grind. Cam was similar to a 1968 340 4 speed hydraulic flat tappet, but I don't recall what the LSA was, thinking it may have been 108*.
Pretty simple and basic package that worked well. I did spend a lot of time dialing in the carburetor and some on the ignition curve.
A 904 transmission is lighter duty, generally taking less power to make it work. I used what I had to work with and what I could afford at the time.
I went with 3 inch exhaust for 2 reasons, the first being that I was considering the possibility of going to a gen3 hemi in the future, and the second one was simply the cost was only a few dollars difference from 2.5 to 3 inch at the time.