My 89 westy is leaking a lot of gear oil thru the rear / engine side.  I put in 2 qts last month and I would think it down a quart now after 500 miles.  Yes that much.  Not driving it much till I can get this fixed.  Anyone had experience with removal and fixing?  Should I do it myself or the shop?  I have pulled many air cooled engines but stayed away from trannys as they worked.   Can the seal be pulled with a screwdriver prying out?  What else should be replaced while apart.?  Clutch disk?  engine seals.?  The engine was rebuilt 5 years ago and 25k miles.  Anyone with a brief walk thru?    /   Jack up rear /  support engine front / undo shifter, bellhousing, nose, pull shafts / 
replace main seal on tranny / replace soaked clutch disk / replace throw out bearing? / any engine seals while I have access to the face?/  /that is about all I can think of.  Any thing missed?  I am leaning towards a shop doing it anyone have this done in the past and the cost?  
Thanks for listening.  
Tom Jansen 
Coppell , Tx.