Engineer/machinist Starting out at 42?

I am an Industrial Engineer/machinist by trade and have reached the point in my life where I can pursue my dream at 42. I recently took my 6-pack Captains course and am waiting on my TWIC to submit for MMC. I have done this to start a small fishing guide serve. I have always wanted to work offshore or in the harbor on a tow though. I have tons of mechanical and electrical controls/computer experience. Will these skills be useful to a tow company Is it too late to pursue this? Has anyone else made the career change like this? Thanks in advance for any input.