With a piston stop, you turn the crank until it touches the stop and mark the balancer. Turn it the other way until you hit the stop, make the balancer. Then, you mark right in between those two marks for your TDC. I have a 318 with 135 PSI cranking pressure and the same cam. I locked my distributor in at 38 degrees, so don't be alarmed if your timing is very high. If you are running mechanical/vacuum advance, you will not want to go too far over 14 degs depending on your distributor setup. With your mechanical/vacuum advance added, you may have detonation. You'll need a timing light with a dial on it since your timing cover only goes to 10 degs. Look at some of the threads on how to check your initial, mechanical, and vacuum advance. I'd also get a vacuum gauge if you don't already have one. Set your idle mixture screws for the highest vacuum. The tune takes a while, but is worth the time to get it right.
