RE: Great Planes Trojan T-28
I started one of these years ago. Never finished it.
I tried to make it match the Platt plans from RCM for a more scale outline. I also wanted to make it a "C" model. You can see some of the pencil marks on the attached plan.
One problem was the short cowl. There wasn't much room for engine mounting. I don't know how a modern 4 cycle would fit.
BTW: The manual says to use the CG on the plans. There was none shown on the plans.