Brendan, there was a post some time back about how to mount a modern condenser in the same place a stock '35/'36 condenser mounts (in the hole provided in rear of the coil) and you can't tell if it's an original or not. I believe it was GM who once posted the info with a sketch showing how everything fits and wires up. Unfortunately, I didn't save the information.Maybe Ken Ct has the info. You could send them a PM.
We stock all the early condensers. Their ratings are all similar, but their mounting configurations vary. There were two styles used in 1936. This is the first version (as used from 1932-early 36):
The late 1936 distributor used a one-year only style condenser (#68-12300) which we also carry. Here is a pic of that one:
You won't find these at your local NAPA store. You could use a generic IH200 condenser but it would have to be jury-rigged to mount it and get it connected electrically.