Yes you could do it that way.. Not anything against your idea but it's kind of a "bailing wire and duct tape" route as Dad would say. He would give you almost word for word what Thurmond put. How much more is the next gauge number down?

I feel your wallet fire's heat clear over here. I'm a penny pincher when it comes to most everything, Except electrical.

Try it, the worst that can happen is you may have to keep a close feel on the cables and let them cool. If it's warm you're not damaging them. If it's just barely too hot to touch you're causing the insulation to have a shorter life and it will crack way sooner.

Hope this helps,
ILP