88'5KCSTQ Ticking - lifter or exhaust manifold?

[StevenM659@aol.com]

My 885KCSTQ (I02,000 mi.s) has a ticking sound. I thought it was a noisy
lifter but now suspect the exhaust manifold is loose or gasket is damaged. Is
there is foolproof diagnostic method? The problem used to go away when the
car warmed up, but now is there all the time. The ticking sounds like it is
coming from near the front of the the turbo and not under the valve cover.
Dealer suspects the manifold (over the phone discussion) and estimates $400
repair to pull manifold, replace gasket and resurface. Also predicts problems
with the head it I don't deal with it. How long can one live with this
problem without dealing with it? Any advice would be much appreciated.