The Apprentice ratio of the other guy is not right. I think it's at least 4:1.
You should of had a rate sheet when you bid the project and stated "prevailing or non". I don't understand how you could even consider doing a job that you bid at 14 and hour when your guys are going to make a 40+ package.
Don't forget about all the employer taxes you're going to pay on the wage too. You might want to talk to the local Union about signing a one job agreement. Instead of giving your empoyees the extra fringe money, it goes to the Union. The real benefeit to you....it's all a write off. OR, you can follow your guys to the bank and have them kick you back half their check I've heard of some guys doing it.
Good luck on all your certified payroll too .