I'm trying to set the timing and it shows to put the #4 cylinder top dead on the compression stroke.how do I tell when I'm on the compression stroke?

Remove the spark plug and hold a rubber stopper or blow-gun tip in the spark plug. Proceed to rotate the engine with a breaker bar until pressure is heard/felt passing by the stopper. When pressure is confirmed place a straw into the plug hole and continue to rotate the engine until the straw is pushed out of the plug hole as far as possible. If the straw starts going down, its best to repeat the whole procedure. Try not to turn the engine backwards.

Goodluck

Sorry, the stopper is pushed against the spark plug hole and not the plug as I first posted.

Remove the spark plug and hold a rubber stopper or blow-gun tip in the spark plug. Proceed to rotate the engine with a breaker bar until pressure is heard/felt passing by the stopper. When pressure is confirmed place a straw into the plug hole and continue to rotate the engine until the straw is pushed out of the plug hole as far as possible. If the straw starts going down, its best to repeat the whole procedure. Try not to turn the engine backwards.

Goodluck

Thanks, now where will the distributor be setting with the pistol at TDC?