I looking for ideas on retaining the plug wires
A couple pictures of your setup might help.
Summit racing has a few different styles.
Linnen cord lacing on 7mm cotton covered spark plug wire with Raja ends looks pretty era if that the look you are after.
Flathead V8 Ford sparkplug wire holders look good on overheads.
Les, take a look at how the plug wires are supported on a Continental A40. Basically, there's a simple steel bracket that holds a rubber grommet that the wires pass through, and the whole thing is held to the engine by one of the head studs. Couldn't be simpler, and it's much more Model T-grade than carrying your wires in finely polished tubes with little flares everywhere a wire exits.
I was working on an A40 just yesterday and would have taken some pictures but I'm five hundred miles away from it today.