Jerry,
Okay. So, let me see if I got this right......after the three lines are drawn on the MDF, you cut the clamping jig. First you cut on the outer line that reprensents the top of the trim and then cut on the inner line that represents the bottom of the trim, correct? The line that represents the actual bulkhead (bottom of dado) is not cut but only used for a reference point for the other two lines, correct?

By the way, beautiful mortise and tenon stile and rails on Destiny's electrical panel cabinet!!

Your fiddle rails look very similar to mine. I'll post photos some time.