Note the Chris method works but only in Pa. ;o)

If you use 215x75-15 BFG TA tires, the shoulder of the tire contacts the
outer edge of the dish in the carrier and won't allow the tire to be secured
into the "well".  Here's what Seth of H&R Motors in Santa Barbara did for me
and others.

remove the "wires" that restrain the stock tire.

Trim the rear edge of the carrier dish and use some hinge supports welded to
the front frame rail extension to lower the rear mounting point.

Weld in a spacer on the front of the dish to lower the front mount.

This will allow the Michelin MX series which have round shoulders to fit but
only up to 215x75.

To fit the BFGs  you must trim away some of the outer lip of the dish so the
tire will no longer contact the dish at the tire tread shoulder.

Then...it fits axially.  Radially, to fit anything larger than 215x75 you'll
need to relieve the  weld flanges where the tire tread interferes with the
frame.

Worked for me.  Seth does great work.  I can post some pix to the yahoo
vanagon group.

p