Can't say where you will make it to in a certain time frame but it is a good field. Was a Cobra mechanic and wrenched for a while after before getting into full time flying. Your financial situation matters a lot.
The good news is the retirement pay will help.
The bad news is that is is expensive and can be a rather difficult path.
You do have 20 years to play with, so you have a lot of time to make a decent second career. If you don;t have an A&P, absolutely get one. It is a good resume enhancer and fall back in bad times.