I would think that you could figure it out by putting a degree wheel on the crankshaft. Then rig up a pointer out of wire or something, and get it pointing to zero when #1 cylinder is at TDC. Then rig up a dial indicator on on one of the valves for your #1 cylinder.

Then you get the specs for your camshaft. Rotate the engine by hand until your valve (intake or exhaust...shouldn't matter)starts to open. Check your spec's to see at what degree of crankshaft rotation your valve is supposed to start opening or closing.

It should be fairly accurate....but IMO it would just be easire to take the timing cover off

my .02


Bryan
1954 3104 235 "AD" L-6 3-on-the tree