Welcome! Glad you joined.

Are you in Charlotte? I ask because we have a map (Bullnose Forum/Member's Map in the menu) and we could add you if it really is Charlotte.
As for the mechanic, is he supposed to be vintage? (Sorry, couldn't help myself.

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On the brakes, it sounds like the brake booster has a leak. There's a test on the page at Documentation/Driveline/Brakes and then on the Overall tab and the General Brake Service tab. Then scroll down to Page 5.
If the brakes work then it isn't urgent that you get that fixed as I've been around these trucks that have had that wheeze and they worked fine for years. But I'd bet that's the problem.
On the dash lights, are the gauges just very dark? Or are they out? If dim, there are lots of things that can be done to help, but the usual issue is that the blue-green "filters" have gone opaque. They are there to give the lights a blueish tinge, but they get old and won't transmit the amount of light they should. They can be removed and that will add a lot of light.
But, I think that the best approach is to pull the filters and install LED's. I've done a bunch of testing on a thread called Instrument Lighting & Paint Testing. But
this post might be the most informative.
Gary, AKA "Gary fellow":
Profile
Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI