HI Tom
I think I would do it the same way with the same jig ,with floating type tenons , just need to use the router table and make some tenons with a round over bit and some hardwood....cut them off to the right size and glue and glamp them it,,because they are so big I would put 1/4" dowels pins in to lock them in place..one would do the trick but 2 would look better I think...
in each floating tenon joint....
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