Honda Repair: timing belt repair, crank shaft, honda civic

Question
I had a timing belt replace  and now my #1 plug blew out and they say they dont have to take out the plug to do the timing and make sure it top dead center i need to know if their any reason why the plug would have to be pull when doing the timing on a 95 honda civic DX Thank You.

Answer
 Well one way to check top dead center is removing the number one plug while rotating the engine you have to lace your thumb over the opening and you will feel the air pushing out then your at top dead center. Now you can check top dead center by rotating the engine and checking the timing marks on the timing cover right over top of the crank shaft pulley theres a white notch on the pully line it up with 0 then your good as well.