I plan to borrow a copy of Solidworks and Mastercam from a friend of mine who is in the business, to try to learn how to do this the right way. But I won't have time for that until after Drag Week.
I hear you on the maintenance thing; the local service organization for Haas charges $125 an hour, including the trip time. Fortunately they are only 15 minutes away from me. With luck I can avoid calling them for a while.
Excellent choice on the software, I think you will like that and will pick it up quick. If you're using a friends copy it sounds like you've got some good help right there at hand too, which is great. On the Haas service being 15 min away... SCORE!
If you get rolling and purchase your own copy of Mastercam I can't recommend strongly enough to get the solids module. Soildworks may actually be a little easier to use but not by a lot and unless you're getting it for free I think the module will be cheaper. I'm programming pretty much everything using solids these days using only Mastercam and I've found I'm way faster and more accurate because of it. When I go back and look at some of the old stuff done with wireframes I almost can't believe I got anything done that way. Sheeze, the difference is huge.
Here are a couple screenshots of car stuff I've modeled in Mastercam recently to give you a bit of encouragement. One is a rocker trim clip I made for my Galaxie since the ones I needed aren't reproduced by anyone. I cut them from 1/2" nylon sheet on the 5 axis mill in a single setup leaving the completed part attached to the remaining stock by a small tab that snapped off easily by hand. The head model took longer but I made it accurate to my heads and was able to use this model to plan the best location and proper cut depth to CC my heads before making any actual cuts. You can do just about anything you can think of with this stuff, I'm excited for you getting going!
