...That's quite a Plan! I Think You Covered Everything. Gonna take Awhile. Good-Luck with it! It Will Be Fun!
To add a little Note...on the '74 Pantera, the Factory Fuel Gauge, Already has a RED Light Built Into the Face. It Comes ON at Aprox. 30 Miles of Fuel, Left. 'About' 2 Gallons, by My Experience.