I just went through the tranny rebuild thing, 2nd gear issue. I changed the tranny lube prior and replaced the motor mount, neither fixed the problem. When the mount goes bad the entire motor lifts in it's "cradle" during acceleration. The torque transmitted in the driveline lifts and drops the motor on it's mounts. When this occurs the slack / tension in the shifter cables (there are two of them going to the tranny) is affected which could cause your problems. An easy way to tell if your mount is bad is to have someone watch the exhaust tips as you let out the clutch and pull away. If they tilt downward a bit your motor mount is likely bad. Good luck......Mark.
