Career Change Advice

[balistidae]

Hey everyone, kind of a random post but I thought I would give it a go. The deal is I am Journeyman automotive tech working at a local Toyota dealership. I have been doing this for about 5yrs and I am making good money but it is definitely time for a change.
I just cant take flat rate anymore, it is an extremely difficult and stressful way to make a living. Some days you go home with 18hrs and the next day you could make 1hr. Aside from the pay structure there are no benefits or pension plans or any of the like. I would also love to get away from the stigma and questionable ethics that unfortunately go along with the automotive trade.
So my question is how do you get away from a career that you thought you would have until retirement. I can see myself in any field from IT to the environmental sector. I am willing to take some classes but I will also have to work full time as well. I've got a gross mortgage and am getting married in 6 months so full time student is not really an option.
I just need to make something happen while I am young and motivated and childless haha.

Any help would be greatly appreciated. Thank you!!