Nobody's mentioned it yet BUT since you are using a 904 trans why not put in the lower 1st/2nd gearset from the A-999 transmission so you can run a higher rear ratio for the freeway? I think from what rumblefish360 said you could use a 3.23:1 ratio and from a stop it would accelerate more like it had 3.55:1 gears. If I don't swap a 4-speed and 3.23:1 rear into my Duster I'll probably rebuild the 904 with a ~2500 RPM converter, A-999 gears, and shift kit and put in a 2.94:1 rear.
To put it in perspective I'm going to rebuild my 318 at the same time with its current cam but with RHS Magnum heads (LA intake bolt angle), 1.6:1 rockers on the intakes for around .480" lift (cam is already dual-pattern so exhaust lift will be around .475" with 1.5:1 rockers, from what I've read is plenty for Magnum heads), headers (Doug's or TTI), zero-deck pistons for around 10:1 compression, and a port-matched Edelbrock Performer (non-RPM) intake for better gas mileage and low-end torque with the auto trans. I'll probably run a DemonSizzler-tuned SB ThermoQuad as well. Then if I want to take it to the track I can swap in 3.55s or 3.91s as well as an RPM Air-Gap intake and 650 cfm Holley and see its true potential.