Extend the fork to the full length, the bolt should bite. Alternately use a piece of dowel (broom handle?) and put it down the open and to hold the bolt against the fork leg.
well crap. i got the drain bolt off on the right side just fine. but the bolt on the left just spins in place. i also can hear the spring moving around inside the housing when i turn the bolt. even tighting it just spins. the alen head is not damaged so the 6mm alen tool still works. any idea's?