OK, now I think I have an idea what you are trying to do.... Are you trying to rotate the dish east using the Uniden and the actuator motor until the elevation angle of the dish is the same as the satellite located at the orbital slot 58 degrees West (IntelSat 21)?
If so, for your location, the dish elevation angle when aimed at Intelsat 21 located at 58w will be 46.7 degrees. This elevation angle will be read on the face of the dish from top to bottom or top to bottom on the on the dish mount ring. Here is the calculation from
www.dishpointer.com for your zip code.
The dish elevation angle for the top of the arc for your location is 56 degrees, so I also have no clue what you are measuring to measure an elevation of 58 degrees. Where are you placing the inclinometer to read 58 degrees?