I think you need more than "fire truck" to make that one work. Especially since the original version is in red. Even a new head is going to leave it pretty far from the original figure.
Why would you wish that on yourself?
Just like Inferno, you're dealing with a base mold that is already primarily the color you want. You'd be adding some black to the arms and head and some orange to... I dunno, the grill?
I think the Skid-z and Mega-Octane ideas are both sweet. Would happily pick those up. The jets sound fun too; Skyfire out of Jetfire sounds amusing. Dark Skyfire is similar in a few ways, but it can be easily played up enough to make each unique.