twin 454 and one rpm gauges is reading higher then the other. but the sync gauge is reading that the engine is slower then the other one. to equal the sync gauge we advanve the throttle. but now rpm is 1100 and the other is 600? any ideas in where the culprit lies. faulty gauges?

Check the "cyl selector" on the back of the gauges to make sure they are pointing at 8.
Not 4 or 6.

now that i have the instrument consol apart, the rpm gauges are perfect? but the sync gauge is all over the place! i suspect a new one. man what a wire mess!

Choose a high cruise speed (3600-4000rpm).
Sync by ear.

Check your tach readings. They should be within 75 rpm (stock tachs aren't always very accurate).

Sync gauge should be close to even (there is a screwdriver adjustment on it to tweak it).