Both good shifters and yes to the Merklin bushing trick. Wish I knew about that when I did mine.
Wear gloves and pull the carpet away from the hole. Put some rags down to keep the grease off the things you want to keep clean.
I bought the Vintage (short handle, no bend) and it was an easy install. The old shifter pops out after you back off the two bolts that hold it in. Put the dirty end in a plastic bag and set it aside. The new one has a cast base with a grease fitting. I greased the ball and cup, dropped it into place, tightened one allen bolt a little, realized I'd missed the cup, and tried it again. Third time was the charm. Initial adjustment was easy.
The Vintage Speed shifter starts out a little tight. Sort of has to "wear in."
In my case it worked good and then drifted out of spec. I'd find myself with no 4th gear from time to time, usually after giving her some gas in 1st and second. I thought I wasn't getting the allen head bolts tight enough so I replaced them with 13mm hex bolts. Turned out it wasn't those that were loose, but the bolts on the trans mid-mount, which I discovered a year later. Tightened those up in June and things have been very enjoyable since. Every gear in its proper place.
--which is to say, since you also replaced the transaxle: if you have a mid mount system, check to make sure all the nuts and bolts are snug. A little movement there can make for soup shifting.