It's not that hard to replace the thing, two of the bolts, as memory
serves, are easier to get at laying inside the fan than from the rear.
You might consider replacing the thermostat itself while you're in there
depending on price.  Mine sat for awhile and it was the gasket, but
figured I didn't want to open it up again any time soon so put in a new
thermostat - don't go cheap on it tho or you'll be sorry later.

Good Luck,
Tonya
87 Vanagon GL Wolfs