First of all are you good at landing? If you land 'softly' 90% of the time then you do not need to strengthen the Fuse.. The planes fuse is only "weak" when it's on the ground..
The one thing on the fuse to worry about is the landing gear! it's really weak. all you need to do is lay some Fiberglass over it and Coat THE WHOLE LANDING GEAR AREA WITH EPOXY! Also it wouldn't hurt to lay a layer of epoxy in the tank compartment for fuel proofing purposes.

The firewall is a different story. See if yopu can't pop it off the fuse and sand the contact area's down... then EPOXY it in there! then use the tri-stock
TIP: it's easier to install the tristock while the Firewall is off.
Now you COULD pin the firewall using toothpicks... Not necessary but good peice of mind..