If you're going to consider building a full size "Too Much" you might consider buying a carload of balsa first!
For two Brodak 25's I would consider a Gordon Delaney "Path Finder Twin". Even though the original had two FP15's, I was told that later it was converted to 25's and longer lines and was even better than it had been originally.
Another potential candidate for two 25's is Bob Whitely's "LA Heat" . Eric Rule, "RSM" makes a very good kit of it and it's still the only Twin to ever make the top ten at the NATS. I was told that it missed the top five by only a couple of points. A Great airplane! Bob's original used two OS 35S engines, and the Brodak 25's are probably a pretty good match for their power and weight! It's about 800 sq. inches of wing area but not as big as the "Too Much".
Randy Cuberly
PS: If I ever get around to it I intend to build one for two FP25's.