[Tim Walsh]

Jamie,
I think your method would work well if it was a noninterference motor because you're assuming that valve is always at maximum lift, but I expect if you actually run the "experiment", you'll find you'll come up with a negative number! Dave and I have thought about this before as well and never came up with a good solution other than to have the head/cam tower assembly all bolted together. There's just too many variables in machining to do anything other than the lash adjuster method, or clay method.