The only adjustment is the shift rod. And the bearing under the lever, too, i guess.There is a procedure in the bentley, which i don't have in front of me now, but i could maybe scan those pages.But to me it sounds like the rod has slipped within the clamp where it meets the linkage.Make sure the transmission is in neutral. Take the boot off from under the shift lever. Loosen the clamp at the end of the rod, and make sure that the thing on the bottom of the shift lever is exactly in the middle of the reverse lockout. Then tighten the clamp again..:Sent by pneumatic tubes
If you happen to have an old tape cassette case it is the perfect thickness for setting the shifter the correct distance from the stop. Make sure you also adjust the throw length (by how far onto the shaft the clamp sits) or you can damage your transmission by not allowing the gears to fully engage. You can check this by making sure that when a gear is engaged, there is play in the shifter linkage at the transmission. Once the gear selector pops into the gear, it needs to be a bit loose. Hopefully that makes sense, it's been a while since I worked on a MK1.
I am using the missinglinkz products. USRT isn't getting any more of my money.