[Steve Davis]

Terry, you are correct, the back of the arch has a groove the wraparound fits into. The model 20 did not have this groove, they used a rabbit joint (a groove that extends all the way to the edge).  Those are a real bear to assemble. When I make a 20 cabinet, I make the rabbit cut about one half inch wide to make assembly easier. I use bar clamps and a ratchet strap to hold the cabinet together while the glue dries, then trim the edge after assembly.  It's very obvious why Philco starting using a groove set in from the edge on the 21 and later cabinets. As for the wraparound grain direction, the model 20 used an up and over grain direction while the 21, 70 and 90 mostly used a front to back direction. I say mostly because they did use an up and over on a few 70 and 90s.  In the past, I did own one 70 and one 90 with up and over grain. As far as I know, all "Clyde Shuler" style cabinets had front to back grain.

That 18MX trim would be a tough one. My moulding head is only two inches wide, so the best I could do is make it in sections.

Steve