Robc,
It's a lil heavy, Tom recomends a 5lb engine if you don't want to start creating new places for batteries and rudder servos. The 5.8 will certainaly fit and the Giles can take it. This plane is built like a Russian Tank. But be watchfull of the CG and make sure you have everything sealed against flutter and I would buy some stock in either Loctite or Permatex as I am sure you will become quit familiar with their products.
Good Luck.
JDS
