Look at this distributor cap I have. Mine is just like this but it is tan. I've already installated the oil pump driveshaft, the distributor, cap, and rotor the way I thought was correct. But I want to be 100% sure timing is dead on 10 degrees BTC when I go to install the engine and crank it. I'm sure the piston was at TDC when I installed the driveshaft. But using this weird cap I'm not sure which side is #1 on. See it has an arrow pointing both ways and says 1 at each end. How do you know what is #1? Is there any positive way I can make sure this timing is about as close as I can get to correct. It's a stock 400-4bbl, stock ignition. Click on the pictures of the cap to see what I'm confused about, that's the one I'm using but mine is tan.
http://www.autozone.com/autozone/catalog...ndName=Duralast

I would bring the timing marks slowly up to 10BTDC & not turn it backwards (if you go past turn it back to 20BTDC then creep up on it again) & plugs out for this helps. With the vac can pointed roughly where you want it and a reluctor tooth lined up with the magnet slot continue to move the housing slightly (CW) so the reluctor tooth is a hair past being centered on the magnet.

Plug wire #1 is where ever you want it. As long as the plug wires are in the correct order, the ignition system doesn't care where they are.

Put your timing mark to 10* BTDC on the compression stroke(pressure building when you hold your finger over the #1 plug hole while turning crank). Then where ever your rotor is pointing, you twist the distributor until any terminal in the spark plug car is directly over your rotor's tip. THAT is now your #1.

I'm actually having trouble finding out if I truly have the engine on TDC now that I have the valve covers on. I did attempt to set it at TDC with the valve covers off and while looking at the valves but I couldn't see any noticeable change in the way the valves were so that method didn't help me in determining if it was on exhaust or compression stroke. I went with putting my finger over the #1 plug hole but it seemed to me that no matter when I was turning it there was always some air coming out. I still could've been wrong because it was hard turning the crank and putting my finger over the hole long enough to tell how much air was coming out. I've seen tools available that help indicating TDC. Should I get one or is it worth it?

Looking at the valves, they're in order by EIIEEIIE.

Crank it over and watch the intake valve on the #1 cylinder. After it closes, bring the damper to TDC. That will be TDC on the compression stroke.

Now put the distributor/intermediate shaft in where ever you want, and the rotor will be pointing to the terminal for #1. Then go in normal firing order from there.

rotate the engine over, paying attention to the valves. there'll be a period of time when neither valve is moving, the first valve that moves will be the exhaust, then the intake. TDC will occur when the exhaust is closing and the intake is opening (split overlap) That's not the one you want. After the intake opens and closes, pay attention to coming up on TDC and set the damper to 10 BTDC. Now mark the distributor housing where your number one wire is and make sure the rotor is pointing in that direction. Then make sure the reluctor is lined up with the point on the magnetic pickup, if it's a mopar unit. If it's an MSD or Mallory unit, go until it's halfway past being lined up. It'll fire right up if you have fuel.