I see this post goes back a few years??? Anyway, about 2 years ago I decided to try something different with my trans. Bare in mind that my car is mostly street driven, but sees about ten races or so at the track each year. I had run stock tranny's, Pro shifted 18 splines and slick shifted tranny's without the brass syncro rings. The tranny that has been in my car now for the past 2 years or so is a slick shifted 18 spline with the brass syncro rings. The main gears for 3, 4 and 2 are slick shifted.(every other clutching tooth removed). The 1/2 slider and the 3/4 slider are also slick shifted, BUT they are a stock slider for the newer syncro assemblies ('70 and up). I am also using the detent keys and springs installed so they are on the teeth of the sliders. This way, driving on the street is normal, yet when power shifting at the track, the wider "GATE" (with the missing teeth), makes for a very fast shift without messing up the gears. Absolutly no grinding when street driven.