got $800.00 burnin a hole in my pocket...

[Stang_Crazy]

IMO, swapping the intake will give you some power but the heads will still be restricting the airflow so you won't see the best gains. I also think the 70mm tb is too big for a mostly stock application. You'll have better results with a 65mm.

The ideal thing to do would be the heads and intake at the same time.

Actually, if you get rid of those long tubes for some shorty's, you'll probably see a nice gain in SOTP (seat of the pants) feel. The long tubes are killing your lowend torque and since your motor is basically stock, they aren't necessary. If you end up going with a heads/intake package, those headers will benefit you.