'95 transmission starts in 3rd

Transmission starts in 3rd in a '95 ZJ my son drives. It's the same one discussed here in other threads. I knew it was acting weird and have been expecting the worse, so for the time being I had told him to shift it manually.

Yesterday a hose blew and dumped all of the fluid over the .2 mile he drove before it wouldn't go any further. The hose has been repaired, and it's back to the way it was; shifting manually.

This is not a vehicle I would pay to have a transmission overhauled or replaced. It's at 192k, sat for multiple years, was wrecked a time or two, leaks rain water inside, and much of interior electronics no longer work. Good engine, and a handful of new parts.

I thought I would check here though to see if there is some sort of treatment that might help, or any other advice.

Thoughts?