6.5L Turbo GMC 1997 3500 Savana/Express cut away transmission Q

[007longbeach]

I use a 1997 Savana 3500 cut a way tool van with a 6.5L Turbo diesel, and was wanting it to shift up sooner and not run the engine revs over 2400 rpm unless in over drive. Is there a simple cheat or is this something that I would have to get an after market TCM?

 

I know it only has 190 HP but it does have good torque at the 1800-2200 range and would like to operate it in that range and be at WOT or close to it.

 

Has anyone ever done this before and was it worth it?

 

Thanks in advance.