Hi,

there is an special Tape available. On that tape you can find the BTDC, the ATDC and some degree marks between.
Just pull your ballancer, install that tape on it and reinstall the ballancer.
Than you'll be able to find any timing mark much easier with your timing light and If there is not enough space for the t-light you'll be able to do it exactly by hand

The tape should be available in good sorted perfomance stores. If I remember right it's by Mr Gasket, but I'm not sure....

just an idea...

good luck

Jens