[Grady Clay]

Britt,

Your mechanic is correct, you need to remove the left heat exchanger. The issue is where the exhaust flanges bolt to the heads. How long since it has been off? What condition? Repairing broken exhaust studs are much more difficult than replacing the seal.

Doug is right on; replace both Gilmer belt pulleys and the belt while you are there. You need all three, otherwise a silgle old part will damage the new. If functional, save the old parts for road spares.

jstobo is correct, it is much easier to do this out of the car. However with some patience you can do this DIY while in the car. The worst that can happen is you sheepishly tow it to your mechanic. You get credit for trying.

Be very careful to not damage the seal surface on the cam when removing the old seal.

Best,
Grady