Ash,
Have some advice from a techie who never tried to make the switch (blind as a bat):
1) Don't hang around. The longer you are a groundcrew, the bigger the them/us divide becomes. I don't mean this in a bad way, but the t-bar chats and post work lifestyle are worlds apart. I know people who, after a few years as groundcrew with aspirations to fly, suddenly decide that "they wouldn't fit in". This is not always the case, I've met some guys that went on to be very good front-enders and were very happy.
2) If, in time, you get accepted remeber that you may be chopped in the early days of selection and might go back to your old post. So don't burn your bridges on the way out. A sooty on my last Sqn was accepted for Self Loading Freight and p*ssed a lot of people off with his "I'm better than you" and "I don't need to do that, I'll be in the mess soon" comments. Imagine the joy when his former colleagues found out that he'd been chopped and was coming back. It got so bad he PVR'd.
Good luck to you, whatever you decide.
TLS