Hi,
I have been out of the aviation loop for some years but I do remember during my time at Bond in Aberdeen there was a co-pilot on the S76 who had started with the company as a groundcrewman.
Just after I left the company he was promoted to captain.
Anything is possible if you work at it and get a little bit of luck on the way.
For what it is worth, I joined the British Army as a groundcrewman and had climbed to the dizzy heights of Lynx aircraft commander when I left for the North Sea in 1989.
Best of luck to you as you climb the ladder mate and remember - whatever you do in aviation - enjoy it.
Opfixclear