This plane will have brass sides dovetailed to a steel sole. The side plates will have the tails and the sole will have the pins (to resist the wedge trying to push the sole off). I’ll probably do this just like wood dovetails, using a silver bearing solder as the glue. If my pins are sloppy, I’ll lightly peen (ie smash the metal into the gaps) and then solder. As a soldered finger joint seems to be strong enough, dovetails are mostly for visual appeal (ie if the sole and sides were the same metal, I wouldn’t go to the extra work).
This photo shows the evolution of the side plates: the drawing, marking the tails on a plate and the machined plate.
You might notice a “factory floor” plan change; I machined the first pair of plates (I’m making two planes), eyeballed it and decided to change the spacing on one of the tails.
Here, I’m gang machining a pair of plates with a 60 degree (30 in wood speak) dovetail cutter (1/2” wide at the widest, 3/16” tall). I first removed most of the waste with a regular end mill to minimize wear and tear on the dovetail cutter. Real men do this operation with a hacksaw and files (see Bill Carter’s Technique’s).