DO NOT provide the parts, but have your mechanic/shop buy it to your spec...that
would be like bringing in a raw steak to a restaurant and asking them to
cook it for you...with a warranty that it will be a good steak...
Also, make sure they put in writing their guarantee. Normally a
time and/or miles (the parts supplier should also have a warranty)
DO NOT tow until you have a min of 500 miles on the new gear set and make sure
the shop includes the price to flush it after 500 miles
Use synthetic lube with Moly...only if it is an open diff...if clutches of
any kind...then no super lube...just straight up synthetic