Ford 3930 lift

[Rare Breed]

I am restoring a 1995 3930 with 8x8 shuttle tranny, that has dual hydro pumps and deluxe remotes. I have tractor disassembled to paint. Remote hydraulics where strong, but 3 point lift was very weak(full rpm's barely lifts weight). I should have tested rear housing mounted pump before teardown. This is one of those projects that started small and is now a full blown restore. Thus far I have replaced lift cover orings, priority valve orings, lift cylinder orings and have removed hydro pump for visual inspection and check orings from filter pick up tube(has external rear housing mounted hydro filter). My question is there any way to test pump off of tractor. Trying to keep from having to wait till tractor is reassembled and painted to find out pump is bad and have to drain oil and teardown again. Tractor has 4100 hrs and hydro pump appears to be original. With that many hours, part of me says go ahead replace pump and be done with it, but trying to keep a budget and those pumps aren't cheap. Looking forward to hearing from the knowledgable members on this great forum! Thanks- Brent