Chris,

The attached photo shows a device that makes it easy to determine the location of the minimum combustion chamber volume (TDC) within a degree independently of any existing front pulley or flywheel markings.  Connect it to a spark plug location and just rotate the eccentric shaft to the point where the soap bubble in the clear tube is the highest.  It might be worth a try.  I made up a number of these to give away at the Paducha fly in last summer.  The lack of interest was surprising since I couldn’t even give them away. 

Steve