I dont know what tire you have now.
But a lot of the newer tires are shorter and wider, somewheres around 24 inch diameter.
Try to stay around 26 diameter of at all possible.
The shift linkage probably has been hacked all up and cobbled back together. It is just sloppy or not adjusted or adjustable.
The late vanagon did have a 5 speed. It dont fit a type one.....but if you want to badly enough anything is possible.