the idle tubes stick down into the idle wells, the wells have a level of fuel, the tubes must stick down into the fuel, how much do they stick down into the fuel? I do not know because it is hard to measure but I would think that ther is not much of a margin. I would say that I have filed about .030 off the collar end and put them back in and they worked. If the ends get out of shape too much, I have rolled them in between 2 pieces of steel and it kind of straightens them out enough to where I usually can get them to fit back. I had some problems with this for a while until I realized that I needed to trim the sheet metal screw. Using a flat file I filed down the sharp tip enough so that it did not interfere with the tube so much but was still at a dimension so that it would still grab the collar AFTER I had carefully tapped down the tube with the small pin drift (.090 diameter). Most of the time it works perfect. sometimes you get a little too overzealous and tap the tube right through the collar. Sometime you screw everything up so bad that you have to throw the whole tube and collar into the trash. (LOL). ...its ok, Cliff sells 'em.
