Isn't there enough money to be made wrenching? I worked flat rate in Honda & Acura dealers for years before opening up my own independent shop & Honda was the place to be. The grass isn't always greener on the other side. I'd start by being honest with youself & ask what it is that makes you want to do something different. Is it the true passion to do body work, or are you just unhappy at what you're doing now & look to that to make it better? I've always loved doing bodywork & making something look new again, but that's been my hobby I do for the enjoyment. I don't do it for money because I don't want the business end of things to spoil my enthusiasm for it. There are plenty of work hazzards to deal with on both sides. You will pay a price later in life for either with sore joints, hearing loss etc. Are you unhappy because of the ups & downs of flat rate? Well more & more body shops are working flat rate every day. So that may not make you happier in the end. I'd think long & hard about this & be honest with yourself as to what you really want.
The grass may look greener, but it may be growing over the septic system & it still needs to be mowed!..
Good luck with your decision.