Problem with Milenco Plus Wheelclamp

I went to collect my van from storage and found that the winding handle on my wheel clamp didn't "pop out" when I turned the key. No amount of key twiddling or tapping with a spanner would shift it and there is a paper thin gap down the side so I couldn't prise it out. The problem was almost certainly caused by my lack of lubricating it but afgter 30 minutes I was ready to give up. Then a light bulb came on over my head and I opened my drill case (used for winding the steadies)  and luckily I had a few drill bits in there. I drilled a small hole in the winding handle and inserted a screw taken from a rear light, just a few threads, and this was enough to pull the handle out of its recess. The hole was only about an eight of an inch deep but now I know what to do next time although it is now suitably lubricated.