If you want a 1/5 scale or 1/4 scale ERcoupe, contact Dave Reid, of Reid's Quality Model Products. I designed the 1/4 scale back in 1976 for the Quadra 35 engine. It has a 90" span and weighs in at about 18 lbs.

The 1/5 scale has a 72" span, slightly smaller than Nick's at 80", and I designed it for the G23, with a 15x 10 prop.

Dave has plans, and maybe kits. Don't know for sure about the latter.

I also designed a 1/3 scale, for the G-62, but did not do the plans to that one.

Nick Ziroli and I are good friends. See attached photo of the two of us, along with photo of 1/5 and 1/4 scale Ercoupes.