Keith, the jig will handle the job. Your router came with a 30 mm guide bushing and you will build your jig with 30 mm between the bars. With a 1" plunge cutting bit all you will need to do is square up the corners of your mortise with a chisel. Clamping your jig across the work piece will let you make perfectly square cuts on the tenons. I will be building this jig on Saturday and will take a couple photos showing how to use it for your project.
"Living in the D" (this means Detroit!)
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