"Has anyone put attachment points for a tow bar on the front of their
Vanagon?"

http://www.syncrosafari.com/harrylewellen/towing_basics.pdf

that may give you some ideas. Jim Davis has a nicely fabricated steel front
bumper that has your basic, standard tow eyebolt hooks attached to either
side. Nicely exposed for easy access and that bumper is attached to the
frame rails underneath at about 6 or 8 places by bolts.

bob