I took a simple ball-inflation needle and cut the end off to eliminate the side hole. The cutters crushed the tube a bit so I had to use pliers to squish it back into shape a little, and here is how it came out.
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The advantage, as I gather, is that the needle is really small, and can fit down into the gap next to the shim so that all the air is directed under the shim, and none goes out around the shim, splattering oil all over the place. Nice and clean. Of course you have to have some way of letting the air through since there is no trigger. I guess you could screw this on to a triggered valve if you have one that will work that way. Last weekend, I just stood at the compressor and opened/closed the valve at Alvon's direction.
Enjoy!
-- se