Ordered a rotostarter for the matrix as my efforts to get it started rersulted in me breaking the pullstart.
Now taking the engine out, the last allen screw stripped, they were locktighted in (which is good) but were extremly hard to get out. Now, the key has ruined its head. How can I get it off? Drill it? 3rd allen key to do this in the Matrix, the metal just seems to soft.

Is it one that has a big head and sticks out? If so you can use a butane torch or soldering iron to heat the screw and break the threadlock, then use pliers or vice grips to turn it.

If not, use heat anyway, it always helps. You can try cutting a slot in it and using a flathead, or pounding a torx into it that is slightly bigger than the hex. and if none of that works, you may end up using a reverse drill bit or ez out.

Just remember to use heat to defeat the threadlock.

I found the screws I had in my CEN MT2 were really weak, I replaced them pretty quickly with a Stainless set from RC Screws.
These were a big improvement over stock but still paled in comparison to the screws I bought from Nathan Cady (Natedog) recently which are hardened steel and IMO much better quality.
Although he only does a "Kit" for the Savage, he can supply you with almost any size screw you require and his prices are great and his service excellent.

PM me for his email address (not sure if he wants me to display it here)

Or go to this THIS WEBPAGE [link]http://www.twisted-toys.net/products/nate.htm[/link]