NP241 Replace?/Rebuild?/Upgrades?

[Enginebuilder]

So, my 1995 GMC K2500 needs its x-fer case rebuilt. 202,000 miles on it, and it likes to pop out of 2hi when I let off the accelerator, and does NOT like going into 4hi, and forget about 4lo.

First, I was wondering if a lower-mileage NP241 from a more recent year truck or SUV would work? Mine is behind a 4L60E, so it has the 27 spline input shaft, right?

If swapping in a lower mileage unit isn't really an option, where would you recommend getting a complete rebuild kit?

Are there any upgrades that can/should be done to the NP241 when rebuilding them?

ETA: my truck has the floor-mounted 4x4 shifter, which I am lead to believe indicates that it is equipped with the NP241.