Since I started this thread I thought I should report back...
To replace the oil cooler seals on a 85.5 N/A it involved the following:
Follow the procedure on Clarkes and...
1. Drop down the powersteering pump and resovoir.
2. Remove the right stabilizer bar bracket.
3. Not necessary to remove the exhasut header but removing the heat shield gives more room to work.
4. Work from on top and underneath to remove the oil cooler heat shield and cover dropping both out the bottom thru where the PS pump and stabilizer bracket were removed.
5. A very good assortment of swivels and wobbles will be needed to get the oil cooler bolts out and back in.
There is also another thread on oil pressure relief valve consulted due to some questions in this area.
http://forums.pelicanparts.com/showthread.php?t=382099&goto=newpost
At the same time you might consider replacing the following:
1. cooling system hoses since the system will be drained.
2. stabilizer bar bushings since it will be partially disassambled and you will be underneath.
3. Power steering hoses that are leaking.