This is a perfect job for guide bushings. If you don't already have the following items I highly recommend that you get them. The Bosch:
RA1151 centering cone to properly center your sub base plates or mounting plate to the router.
RA1126 quick release adapter.
RA1100 PC style guide bushing adapter that lets you use all PC style guide bushings in your router.
A set of brass PC style guide bushings with all the collars slightly under 1/4" length; available from many sources.
Four pieces of 1x3" set as shown in the Trend Varijig photo are your guides. Hold them down with double sided carpet tape; a small piece of 1x3" attached to one side of your routers sub base plate will keep it from tipping on large jobs.(But you won't need it for the task you described)
"Living in the D" (this means Detroit!)
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