Drill Shaft Coupler questions

[l1jmx]

Okay, we just got out drill motor shaft couplers from SPI @ $25 a piece (UGGH!). Anyways, we're trying to figure out how to make the "spring pins" on these guys work. The catalog page says there's supposed to be a hole for a 1/16th of an inch spring pin and that the shaft coupler was supposed to come with 2 spring pins. In our bag, however, were 2 pins that seem to be made out of solid metal (nothing springy about them), and they are 1/8th of an inch thick. There is no way we're fitting this pin through this tiny hole. However, in spite of the apparant failure of small parts to send us the correct item, I'm sure we've got 1/16th of an inch pins sitting around somewhere. The bigger question is a matter of how one goes about putting this pin through the solid shaft coming out of the gear box. Does anyone have suggestions for drilling out the necessary hole?