Steve, Yeah I checked the clutch. I put a new clutch and pressure plate in it in December and first suspected it for this failure. However it checked O.K.
I found the problem. I went ahead and started disassembling the main shaft assembly.
By turning the input shaft and holding the output shaft from turning in 1st and 2nd, but couldn’t hold the output shaft from turning in 3rd, 4th and 5th I figured I had striped something in the 1st and 2nd gear synchronizer assembly, however, I could not see any damage. After fully disassembling the main shaft it was obvious the external splines on the main shaft and the internal splines on the 1st and 2nd gear synchronizer hub were stripped. Oh well, time to let go of a few more frog skins.
Thanks for your suggestions.
86 CJ7 w/ a 258.