to further the description that cool 1 has linked you to - I set mine by measuring from the rocker cover stud to the slot in the intake cam (slot = 4mm wide, camshaft diameter at slotted point is 50.8mm, distance from stud to shaft = X. Formula = X + 25.4 + 2) I do all measurements with a set of decent calipers and make all measurements to 2 decimal places. I then measure from one slot to the next by simply adding the cam spacing.
This is all because I am too tight to buy the Toyota SST.