There are lots of ways of doing the math and all of them are only partially right... or at least most of them are a partial guess.
Most outages run about 3-4 weeks (some longer ones are still available but they are getting more scarce.) There is usually at least a partial week of training/testing first so most techs are brought in a week in advance, some 2 weeks depending on outage preps... but those are 40 hour weeks. Some techs are let go before the 3 (or 4) weeks is up, but some outages run over and techs are kept longer. In short it is a lot of averaging and guesstimating but average (for techs that are not routinely on the 'first out' list) is probably 3.5 weeks of long hours and one or two of 40 hours. So four outages, if you don't get in on a long one, makes 12 to 16 weeks with overtime and 4 to 8 weeks of no overtime. The overtime weeks give about 80 - 88 equivalent hours (roughly) so you get about 32 to 44 equivalent weeks. Three quarters of a year is 39 weeks, so it is like being employed for 9 months. Get recognized as someone that the utilities all want to keep around, either for work ethic or unusual skills and the length of your stay can grow.
If you live on less than your perdiem allotment and have leftovers, that can add up to another couple of weeks (or not... don't forget to claim it as income if you do!
) Throw in some unemployment and (depending on the states you work) you will do OK... but not great. If your lifestyle is not too elaborate and you put your summers to good use it can be a pretty good way to live.
And to the OP -- yes, your experience is enough to do as well as or better than the average road tech. Just be open to doing things very differently than what you were always told was the only way to do them.