Tom, Woodcraft sells a set with all the collars just under 1/4" for about $38. There is an advantage to this since you can use 1/4" templates for all your jobs. Other places sell sets with some short and some long collars which requires 1/2" thickness for your templates; these sets usually cost less. To my way of thinking using just one thickness for your templates is easier but both ways do work. Note that the larger Oak Park/Lee Valley style guide bushings are all just under 1/4" collars.
"Living in the D" (this means Detroit!)
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