Reading the "official" Lotus service manual TC supplement (Section L.11, paragraph 1) to set the fast idle cam, it says to use a .6mm drill bit to open the throttle and adjust the screw when the fast start is fully engaged.
.6 mm? That's 0.023622 inches. Really? Only thing I have close would be a roll of 22 ga wire (which is .0226). close enough for government work?