RE: Hold cowl from inside?
Not that I know of. What some will do is take an allen driver and cut it. Then splice in a piece of brass tube and solder it. Or even using an allen bit with 1/4" extensions. Dont know how well that would work, just speculating. When I bought my GP Yak54 it came with about a 14" allen driver. Maybe you could buy one from GP or Tower. Sometimes metal suppliers sell hex rod. I wouldnt think it would be too much trouble coming up with something.
Edwin