1----Using a piston stop is easy.
Remove the no1 plug, make sure the piston is "down," and install the device. Unhook the battery ground for safety
Wrench the engine over until the piston stops on the device. You may need to adjust the length the first time you try it. Once you set the length, devise a method (locknut) of making the plunger RIGID. Some aftermarket piston stops do not
Here's my homemade one I built in the 1970's!!!
Now, you are NOT trying to stop the piston at TDC, but rather "down some amount." This is not critical. When the piston stops, make an accurate, temporary mark on the balancer directly below TDC on the balancer.
Now rotate the engine CCW and do the same thing again. You will now have two temporary marks some distance apart. True TDC is 1/2 way between, and of course if your original mark is correct, that is where it will be
2----CAM TIMING. If you know the specs on your cam (cam card) you can estimate that procedure by looking at the factory manual
What year? is your car?
You can download some years manuals here:
http://www.forabodiesonly.com/mopar/showthread.php?p=1970088657
Get into the engine section, look for the cam / timing chain section and there's procedure to estimate chain wear and cam timing. This of course is for FACTORY cams, so if you have a wild duration thumper of a cam, you'll have to adjust the figures.
Here's a random card I found on the www, just to use / example
Notice that the intake (top right) opens at 8BTC. This is an easy figure, because after you have checked the timing marks you can easly "set up" 8--10* BTC. Just pull the valve cover and see if this happens-----------wrench the engine back some distance, and rotate CW slowly watching the no1 intake valve. When you see it move, stop, and see where the timing mark is.
3----When you have checked the above, recheck valve lash. If you do not have adjustable rockers, and the valves are too tight, you might have pushrods that are too long. A valve job, head milling, and deck milling are all things that can change pushrod length
4----Then run a compression check/ leakdown and see what you have
5----If you are satisfied that all the above is right, and try again to fire the engine, here is a good way to set up timing.
First, you need to get no1 on compression, and there are only two ways
A----Remove the no1 plug, stick your finger in the hole, and bump the engine until you just start to feel compression. Then watch the timing marks and bring the marks NOT to TDC but rather where you want initial timing, say, 15 BTC
B----If either valve cover is off, bring the engine around so the timing marks are about 15 BTC, and then look at the no1 or no6 valves. Be careful, because if they are both open, they will be about equal. Whichever cylinder, 1, or 6, has both valves CLOSED is the one which will fire.
Set the distributor in pointing to the no1 plug tower if both no1 valves are closed, or if you used the "finger" method.
If both no6 valves are closed, either rotate the crank one turn, or just set the dist. in pointing to the no6 plug tower.
Now, move the dist. CW (retard) to remove "slack" and rotate slowly back CCW (advanced) until the reluctor wheel tip is right in the center of the pickup coil. The rotor should be "just approaching" the corner of the plug tower imagining the shaft rotating CW
If you do this, and do it correctly, the engine will start and run
