Exahust leak fixed!
 

Turns out that after 3 shops, the 4th one actually knew what the fuck they were talking about. I kept getting told 'blown doughnut gasket' and when I went to order said part from Ford, turns out the v6 models don't have that, because it's built in. 4th shop found out that I had a cracked header on the right side, and replaced it for just under $500. Voila, no more vacuum issue(wasn't ever a vacuum issue, dude just didn't know what he was talking about)

While they were under the hood, they determined I have leaky valve cover gaskets, not a rear main seal leak, so that is next on the 'items to fix list'

I am very, very lucky that no damage was done to the engine running around on a cracked header(the pipe vibrated loose from the inner curve of the connecting flange, so still a leak, but not as bad) And suddenly, I have power that I didn't even realize I was missing, and the car doesn't sound like unholy hell and rattly.

Nice. Hopefully you didn't pay or can get your diag $$ back from the other 3 douche lords.

Didn't have to pay for the other 3. I would advise to steer clear of McDavid Ford on White Settlement Road. The Service tech didn't bother to latch my hood and I was more excited to drive the car and get gone than I was to actually check that it was indeed shut, and had to jerk over to the shoulder after I noticed my hood bouncing. That is not something you want going 65 down 820!

Sadly, this is how a lot of shops operate. Surprised they didn't offer to rotate the air in your tires or a low rate.

LOL! I'm female, not stupid.