Here is another time-tested solution:
http://www.womeninwoodworking.com/ti...ingpoints7.cfm
I have two I made from 1x3" auuminum box glued to 1/4" hardboard. One
other mod - leave an inch or two of hardboard on the "back" side for
clamping, so your clamps don't interfere with the saw or router.
Better yet, leave enough hardboard on each side so you can use one
side for your saw and one for your most common router setup. Trim the
guide with the tool you will be using it with, and the edge can be
used to set the position to your marks.