Well, I tried to respond yesterday - and just before clicking the "add reply" button my computers graphics card decided it would be wise to quit service after it's own fan had decided to give up the ghost :( :( :(
Here I go again - after spending some $100 for a replacement today ...
I use 4-20 lenticular shaped allen screws - which I had to buy at a Harley-Davidson depot, for big money BTW, living in a metric country - into which I sawed a slot and silver soldered a brass wing into. Far superior to the coin driven screw IMO because you don't need a coin at all.
I like the screw rather long, with several rubber washers (made from inner tubing), because this lifts the quiver a good deal away from the riser and allows more freedom in handling. I place the quiver between two iron washers which are ontop all the rubber ones, see pic:
Hope this helps somewhat?
Falk
P.S: Ah, the black color is left over from a sharpy marker - as you call them - which I apply befor hunting, for camo purpose.