Since it's all apart some billet oil pump gears are a good idea. Have your heads checked. These cars are notorious for dropping exhaust seats.
Billet chain guides are a good idea.
I have a boss 5.0 with 9 to 1 compression, diamond coated pistons, ported heads, custom set of cams, full 3 inch exhaust system and 3 gt pumps 3 FPDMS Fore rails and ID 1050. at 20lbs of boost on pump 93 with boostane it hit right at 700rwhp and 640rwtq. sounds low? yes it is because the the tuner had to tune around the fact that the fuel system isn't up to task. going with a return style. should hit 750+ to the tire on pump 93 with boostane. I would like to add this was on a loaded mustang dyno.
LIke its been said, unless you have a built motor with a good amount cubic inches, heads cams, little more compression, then yea you can run the 2.9 on pump. If not, don't waste your time with the 2.9 unless you run big boost, e85 or race gas.
Back in the day people were buying the 2.2 kenne bells and running 15lbs of boost. made 570rwhp. Then got butt hurt when a ported eaton with a upper lower pulley with less power stayed side by side with them. Iv seen it. lol.a big blower on low boost? Don't get fooled by the peak hp. Pick the size of your blower accordingly to your build.