"Fingers!' LOL You gave him fair warning <img src="/images/graemlins/cool.gif" alt="" />

Instead of pulling the safety pin straight out, twist it 'till the seal breaks. Works every time, even with electrical ty-wraps... but it may take 2-3 full lap turns to break those.

In highly corrosive atmospheres,(beach, Marine use, clorine storage, acid bath) pins need to be replaced constantly.
Even using stainless steel pins does't solve the problem,since the pull pin slot in aluminum valve heads also corrode.