The best way is to ask here on the Forum. I see you are in north Carolina. Near what big city? I will contact the only owner I know in NC. We can see who he recommends. I will tell him to post here. You are right about having a trained service tech.
Make sure the dealership has worked on GTs before. Don't let them substitute oils and fluids. It is not a given that Ford dealerships know What they are doing.
My feeling is pillows are too soft and will not distribute force as well as several folded bath towels. And if you ever saw how bony Howard is, you would understand.
Yes tie a string on the bolt. Once you loosen it it can drop down still attached to the wedge. Just loosen it enough so the wedge is moveable. When installed, the wedge catches the back, bottom lip of the battery. When the wedge is loose you can move it far enough to the back so it frees up the...
Go over to Tomy's air conditioned man cave. Or call Soroush. He's been MIA for quite some time. Don't let him give you any baby stories. Or maybe piano playing worries.
No do not unscrew the bolt from the wedge. Just loosen it so the wedge can move towards the rear. When the battery is loose from the wedge just lift it straight out. MAKE SURE YOU HAVE LOTS OF PADDING ON THE FENDER SO YOU DONT DENT IT WITH YOUR ELBOW. Get someone to help you if you can't lift it...
You don't remove it. Just loosen it and lift it off the edge of the battery, then wiggle battery to get it away from the plastic wedge. Lift battery out straight up. Check ground and clean attachment point if necessary and add grease if necessary. When ready, drop new battery in and sit in...