I have an aftermarket timing gear cover with timing tabs on a small block Chevy. I know I have the cam timing dialed in but now I'm worried the TDC marker on the harmonic balancer may not be in sync with timing tab since some engines had tabs positioned differently. Anyone got a trick for finding TDC on number one cylinder on a motor already installed? I have a dial indicator but getting it to read through the plug hole to the top of the piston is going to be a problem.