Transmission stalls engine

It seems like my transmission, T5, 78 cj5 w/AMC 360 is stuck between gears. When transfer case and transmission r in neutral and I let out the clutch the engine idles fine as soon as I put the transfer case in any 2H or 4H and let out the clutch engine will die but it seems like it want to move forward.

5 speed on floor sick shift assy pulled all looks good but the nylon sleeve is missing. Can't pull shift rail and fork cover without dropping transmission.

Any ideas?

My guess is you have a loose or sheared off set screw on one of the two forward shift forks. Your correct that unlike the T176/77 or t4/5 must be removed from the vehicle to remove the access cover.

So the CJ5s have no trans hump cover that removes?

I think the earlier ones did. 76 up don't though.