I can't comment on the Evo 26GT, but I have the Skyshark Edge. Mine balanced just a touch nose heavy with a YS 1.10, Tru-Turn Spinner and 625MG Servos. Three things concern me using a heavier engine in this plane.
1. The firewall is not strong enough without significant re-inforcing. It is made from very soft ply that crushes easily. I pinned mine, but the rest of the box would also have to be reinforced as well.
2. There is not much room to move gear back. The center mounted wing takes all avail space behind the fuel tank. You could move the elevator and rudder servos back, but as is, there is only light balsa sheeting in front of the tail. You would have to completely re-engineer the tail section to move the servos to the tail. The Electronic module and battery could only be located on the engine box compounding your nose heavy situation.
3. This plane only has 689 sq inches of wing area. Mine came out a tick over 8lbs with the YS 1.10. It flys great, but it's performance would decline quickly with any more weight.

The Saito 125 would be a good choice.