trans slips

I have a 98 mpv this for a friends 92 mpv when cold first shift is hard it does not slip till it warms up. I was going to have a friend rebuild it he is retired but some one broke into his storage unit stoled his tools he cannot afford to replace the tools. I have not rebuilt auto trans in 20 years. I want to know if anyone has a sorce for tech information or manual. It has 175,000 miles was used to tow something don't know what they got money's worth. have been told 89-92 were weak are thier upgrades.
thanks
1992 mpv 2 wd