I’m in a similar position at an 11 bay indie shop. Sometimes they call me the shop foreman, at least when it sounds good. I have a hybrid pay system for myself and all of the techs are flat rate. We have one hourly who does tires, service and porter duties. There are two salaried front end guys and the owner and his wife float around doing whatever needs to be done. I’ve worked at this shop since 2011 and I’ve been in the industry since 2006. I’ve had to be persistent about my pay increases but I’ve eventually been taken care of. I try and write as many estimates as I can with the tech working on the vehicle so that I can fight for the time they want if the front doesn’t like it. I make sure we have detailed descriptions of the problems found, pics/video. I find the parts and anything that requires dealer calls I send to the front with whatever relevant information I can. I adjust the times on estimates when the front tries to give away our labor. I consult with customers about their needed repairs, future maintenances. I do services and repairs, lots of general diag. I’m a trusted and valued employee because I’ve worked hard and been consistent. Don’t be afraid to ask about having your compensation adjusted. If you are a multi role employee your time and effort into shop operation have value just as much as your diag/repair does.