[Dave at Pelican Parts]

As DIY'ers, we have the luxury of being able to spend extra time checking to see if the problem is caused by something low cost (even if the probability is also low). I feel it's worth ruling the linkage out. With Otto's years of experience, he is almost certainly right, but the transmission overhaul is not for the faint of heart, as has been mentioned.

To answer "computers4kids" question about the clutch tube: The tube will move around in the center tunnel, and it can interfere with the movement of the gear shift lever. That will give you problems going into 4th and 5th gear. In addition, often the clutch will not stay adjusted because of the movement of the tube. That will give you problems going into 1st/reverse--or at least a nice "crunch" when you do so!

Unlikely to be your problem. But then, you can take the carpet off the center tunnel and check in there with a flashlight and a mirror or two, just to be sure...

--DD