There is a lot to be said for the Skymaster layout as you get counter rotation props (i.e no motor torque) without worrying about CW and CCW props and no asymmetric thrust if one motor goes down for any reason.
Mine is Depron rather than DTFB and the front motor is switchable from the the Tx.
View attachment 115206
Sounds impressive with both running but it also flies very well, and for a long time, with just the rear one.
Plans? It was built from a particularly detailed 3 view down loaded from the internet, suitably scaled up and tile printed.