The rebuilt TB stall will be fine for what you are doing. Yes, it is true that only a few more hundred RPMs can be squeezed out of it. It would take it to about a 2600 stall. Your truck can push it to the 2600 limit no problems. It is just a "beginners converter." Try it and see how you like it.

Doing a converter swap is gunna be a decent job for ya if you have never done one before.