Addition (after some thinking):
The new dish-angle would indeed (only) be offset angle plus 2.9, as danristheman wrote.
I'm trying to visualize the new value for your inverted scale. That would be offset angle minus 2.9; if I'm not mistaken.
If you leave the scale part on the pole, and just invert the dish to upside down (if that is possible with your dish), the new scale value depends on the angle of the construction between pole/scale part and dish. These parts are not always parallel....
A couple of suggestions. The first is to use the sun to see if you actually have line of sight to 30w. Otherwise you are trying to do the impossible.
There are a few web sites that will tell you when the sun is at the same position as a satellite. Here is one: http://www.satellite-calculations.com/Satellite/suninterference.php
Enter your location and select Hispasat. Scroll down for the results. It looks like the max outage period for Colorado will be around March 4th to 7th. At the peak interference time, see if the sun is hitting your dish. If it isn't, you won't be able to receive the satellite. Ideally the sun should have been above your neighbors house for a few minutes before the peak interference time. Otherwise the beam of your antenna may be picking up too much ground noise.
You can also use the sun to align the dish. I taped small mirrors to my dish and at the peak interference time aligned the dish so the sun reflections were on the LNBF. (tip of the hat to polygiver for this idea.) I bought small craft mirrors off of ebay, about $5 or $6 for a half a dozen. This got me almost dead on, I was able to blind scan in many of the channels.
The first photo is of some mirrors on another dish, just to show what I did. The second photo is of the 1.2 meter dish pointed at 30w, at the peak interference time.
If the dish was inverted and the reflector is straight up/down (angle finder on reflector vertical axis reading 0 degrees), the dish would be looking at point 22.6 degrees below the horizon. To aim at 2.9 degrees above the horizon, place a straight edge on the vertical axis of the dish and tilt it back to set a angle of 25.5 degrees. Offset Angle + Satellite Elevation Angle = Reflector Surface Elevation Angle (22.6 + 2.9 = 25.5 degrees) or (25.5 - 22.6 = 2.9 degrees).