I believe it's possible to drop the pan on that one with the engine in the frame. It might be necessary to loosen the front motor mounts and jack the engine up a little to do it. If you do, be sure to remove the distributor cap to keep from breaking it against the firewall as you raise the engine. (Guess how I learned that trick?)

If your "mechanic" isn't convinced there's a problem, it might be difficult to get him to do that. Good luck!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!