TBI tuning "window", and engine vacuum variables

I have a 94' K1500 that I am going to swap a 1999 350 Vortec into. I will be using the GMPP 4 barrel intake with TBI adaptor, a bored throttle body and some more yet to be determined stuff.

My rig may never see the north side of 4500 rpm, cruise is about 1800, and I'm after TORQUE in the 1500 to 4000ish range. I have read a ton of info, some may be good and some (a lot) doesnt seem to apply to my application. I plan to run the "395" Marine cam. I have seen a couple cams I like a lot, but wondering how much tuning capability is available with my PCM. Cam duration would still be in the 205 int/215 exh range.

I would appreciate input from you knowledgeable Gents before I start buying parts. I'm aware of the valvetrain issues with the 060 heads. I haven't checked mine yet, but will for clearance issues before I do the cam change. I will be running LS1 ( I think?) electric fans, 3.73 gears, stock sized tires, 4L60E trans. EGR required.

What problems might I run into making this work with the 1994 ecm?
What might it take to optimize my tuning when its running?
Can I buy a chip ?

Thanks guys!