I'll see if I can't work something up for you...
Much of the grade up to Chattanooga is under US 550. From the loop up to the Silver Ledge mine I believe the grade is downslope from the current highway alignment, but is covered in places. US 550 is again on top of the grade from the Silver Ledge Mine up to Red Mountain Pass Summit (Sheridan). From Sheridan, the grade is under US 550 until you start the descent, where the grade takes off and wraps around the North slope of "The Knob" into Red Mountain Town...