Should I re-enlist as a 12C or reclassify to a 91B?

91b is a good mos and it can make you money when you hwt oit

Look at the points for promotion and take that into account.

If you’re looking for recs I do rec 91B I’ve enjoyed it and I’d do it again that’s my MOS right now and it’s helped me a lot to go to school and be able to study mechanics (diesel mostly) and it’s helped me get a sturdy job

Do they still have 12 Chucks in the Army? I was one back in the 90's.

Yeah, 220, 221. Whatever it takes

Think outside of the box, don't limit yourself to only a couple of jobs. The Army has a great deal more to offer than just two jobs. Think quality of life and skills to carry over into civillian life. I say reclass but not into vehicle maintenance, open your options. Big money in aircraft work in the civillian world. Best of luck!