You may want to ask again in the Giant Scale forum. I have the discontinued GP Giant extra 330L 33% kit stashed under my bed waiting for my skills to develope to that level.

I also have the .60 sized version so I can get used to how the Extra flies so I don't take a $3000 dollar model to the field and get surprised as to how it handles.

As to the extra equipment that goes into a gasoline airplane some include

Metalic firewall, and non metalic throttle linkage. (used to limit radio interference.)
Kill switch, (some use both radio and manual switches.)
High Torque and Multiple servo's.
Redundant battery packs. (servo's suck up a lot of power.)
Voltage regulators. (some use LiPo Battery packs for the weight savings.)
2.4Ghz radio setup. (they say 2.4Ghz is not affected by ignition noise.)
Some of your high end fliers use redundant receivers too.
6Volt battery packs. (Higher servo power, and with the computer receivers, less likely to reboot in the middle of a high G manuever.
Don't forget to add oil to the Gasoline.
Good Kevlar or Heavy Leather Glove.

Almost forgot, a trailer to haul the plane around.