Newbie Question - Distributor Install

I have just had a Chevy 350 rebuilt and am ready to install the distributor. I am told that the engine timing should be at TDC in order to determine the location of No. 1 cylinder on the distributor, however, the distributor can be installed 2 possible ways with obviously 180 degree difference. Is there any way to determine if I have correctly installed it before I try to fire it up?
Again, I'm new at this so if my terminology is incorrect I apologize.

Yes. It's known as "blowing number 1". You take the spark plug out of no.1 cylinder. Bump the starter (it takes two people) while a finger is in the spark plug hole. When the compression tries to "blow" your finger out, you know you're up on no. 1 "compression". That's where it must be to install the distributor. Point the rotor towards no. 1 plug wire, and you're there!

Jim