Yes...I was being a wiseguy...sorry for the confusion.

My whole point was that, ASSUMING the engine timing sensor mount holes are drilled correctly - and I will go with that assumption - you only have +/- 1 degree to work with given the construction of the mount upon which the sensor is mounted. Thus, the actual number of degrees of BTDC is somewhat moot, since we are working from pre-drilled holes on the engine case that are assumed to place the sensor within the correct range of timing.

Any timing issues then boil down to whether the timing needs to be advanced a bit, or retarded a bit. Knowing the actual number of degrees BTDC really doesn't matter, simply falls into a "nice to know" category. Now, if the engine came with no predrilled holes and a sensor mount loose in the box, of course we would need then to know the actual numbers so we could drill the holes for the mount. Once that was done, we'd just be back to sliding the sensor +/- a degree for fine tuning the timing...unless of course we modded or built a sensor mount that would allow a greater range of adjustment.