If you put wheels and tires on it that can take the weight, the rest of the truck will do it.
It’ll be slow. And if it’s an automatic (which I assume because you mentioned putting in a trans temp gauge), it may have a hard time ever getting going from a stop on a steep hill. If it’s 4WD then low range will save you.
This is from my experience with a Chevy with a 6.2 and Ford with a 6.9 automatic, which I once had to back down a hill against traffic the wrong way on a busy downtown Seattle street when it absolutely wouldn’t do anything trying to start on a hill but smoke the trans.
On the Chevy I solved the problem by yanking the diesel and putting in a Caddy 500, and even that once refused to back up on a steep hill loaded heavy with no low-range.
However I do have an ‘80s Chevy 4x4 crewcab dually, manual trans, that will walk up any hill under a huge load with just a stock and tired 454, because of gearing.
I think the auto trans is your biggest worry on your truck.
