LB7 Edelbrock heads. Many other mods where to start for low end very low power

Hello, I have been around HP tuners for quite a while but new to tuning diesels. I've been searching the forum and working on gathering information but am looking for a few tips on where to start for the particular problem I have. This is my work truck where I'm towing heavy trailers often and have just recently got it going again after a blown engine. Some short history. Was entirely stock other than AFE intake and MRSP exhaust. It always ran well on a stock tune as far as torque and power from a stop. I blew the engine up on New Years Eve doing a job. Had to get it up and running quickly. Came across a wrecked truck with a GM engine with 60k on it and a built Allison. Bought it and put the engine in my truck, Has Edelbrock heads with studs, Max Flow up pipes and exhaust manifolds. Stealth 64 turbo with high flow air inlet. Basically everything to help it breath easy, Also installed the billet torque converter. As a choice all be it the wrong one I'd purchased the Banks Economind with data monster. Was going to use just this on my mostly stock engine and expect it would have run ok. However with the built engine it is severely under powered off the line Especially with a load attached. The engine runs amazing after the turbo spools up just real slow to get it started. Where I am now. Going to remove the Banks as I'm sure not advised to try and modify the base factory tune with HP and keep the Banks system on it, I like the Data monster and expect that part will stay. As I use this daily for towing I need to come up with something soon to at least help the low end power. Where should I start to do so? I'm willing to learn and have some experience but not with diesels. Any help and suggestions would be awesome. Also anyone else have experience using the Edelbrock heads?

thank you
Mike