bus pump low power?

Hello, I've done some reading and pretty sure I've got my answer, but just to get a straight answer...... is there any difference between a school bus p7100 (230hp) and a dodge pickup p7100? Overall reason for question is I have a issue with my truck where it just does not feel like it has any power and there's very little boost. Specs are 95 Cummins (from dodge truck), bored .040th's over to 6.0, enterprise engine kit, bus p7100, non stock fuel plate, turned up boost screw, torkteknology 50hp overflow valve, 5x14 injectors, 64/74/14 II Silverbullet. Boost gauge is only hitting around 15psi. Truck is a 97 CCSB F350 with e4od trans, banks billet torque convertor and 3.55 gears. I'm also having issues with the PCS trans controller, so maybe the trans is holding the engine back also, but for what the engine has, I can't believe it shouldn't be more powerful.

Just looking for some ideas as what to check, or maybe something wrong in the pump. As far as I can tell I don't have any boost leaks either. Thanks for reading.