Hi 1973vw
Well to start with you are using to big of a router for the job, 3 1/4 HP is over kill

Plus you should not use a plunge router ,it will work but you will run into errors..
If the Jet jig you are using is a 12" one it'a a easy one to setup...
http://www.amazon.com/Jet-709060-12-.../dp/B00006S7CG
It's this most common jig on the market today..
here's a link to a user manual that should help...check both links out..
http://www.mlcswoodworking.com/shops...Manual%20c.pdf
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http://www.harborfreight.com/manuals...4999/34102.PDF
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