The driver's side mirror is set at a 15 degree angle and the pass side at a 29 degree angle - there is no way to change or adjust the setting of the mirror head via the three screws on the bottom - other than to move it to the "tucked" position.

Your mirror covers were actually made for the Rodeo/Passport. These mirrors are made by Ichikoh in Shelbyville, KY. The VX mirrors are made by a Japenese company. Although they look identical, the VX mirrors are slightly (and I do mean slightly) smaller, the mounts are different, and the internal workings are different (which is interesting, since I was told by the guy who did the tooling on the Rodeo mirrors that Isuzu probably spent $60,000 on tooling to "recreate" the Rodeo mirror with a Japanese supplier for the very limited production VX). Your mirror cover is going to be slightly oversized, but shouldn't be noticeable unless you're looking for it. I would think that if you installed the cover while the mirror was in the normal (non-tucked) position, you should not have a problem with the mirror folding. The primary difference in the mirrors is in height - the width is almost identical.