yes you can find a diagram for a manual transmission its under service manuals you need to know what transmission you have go to www.jeep4x4center.com
Most likely the ax15 manual transmission
The ax5, AX15 transmissions in a 1990 Wrangler use 80W90 gear oil.
4 Cyl manual is a AX5 6 Cyl manual is a AX15 Auto is a A904
Half way up the side on the drivers side of the transmission
Drivers side, about half way up the side of the trans, should be a torx bolt.
There isn't one. only an "auto" trans has a dip stick.
Have a donor vehicle for the necessary parts. Otherwise, get ready to spend more money on parts than you thought possible to convert this vehicle to manual. A very simple and wise decision is to sell this Wrangler and go buy one with a Manual transmission. You will be money ahead.
Automatic uses Mopar ATF+3 or +4 Manual uses 80w90
Manual transmission vehicles have no transmission filter.
Yes.. I Have a 1990 F-150 4X4 and it is a 5-Speed Manual Transmission
put the transfer case in neutral .yes
No it does not, unless aftermarket ones are installed