I'm doing the same thing.... Picked up the rare 1991 NP205 with round pattern and VSS a few months ago and grabbed a 4L80e on Tuesday...
The stock adapter is almost impossible to find. If you do find one its big bucks. There is a universal kit that I found on another site and posted over
HERE. It will basically allow you to use any NP205. The only difference on the NP205 will be needing a 32 spline input shaft....
HERE
You will need to figure out your own shift lever(s) with the universal kit. North West Fab has a nice cable shift twin stick setup. not cheap but a nice looking part...
HERE
Here is a link to the original post on the Pirate4x site that has more pictures.... BE WARNED: Only read over there... posting/asking basic questions will get you verbally abused..
CLICK HERE
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