[mr0077]

keith, on the first car, I'm gonna guess that you've got the adjustable stop bolt screwed in too much on the 2/4 side of the shifter, keeping the tranny from fully engaging 4th gear (either that or, God forbid, you may have a tranny internal problem). Both sides (2/4 and 1/3) have adjustable stop bolts...back out the 2/4 bolt and see if it helps.
On the second car, the linkage rods are out of adjustment. There is an alignment hole in the shifter mechanism, where you insert a rod (proper sized drill bit works well). That holds the shifter in the proper "neutral" position. Then you adjust the linkage rods so they just go into the holes on the shifter levers on the transmission...voila, you're done! As an alternative (not very good one), you could adjust one of the rods to get a smooth side-to-side motion, but be sure to adjust the reverse rod so reverse can be engaged in the same (relocated) neutral gate. Good luck!