Hi Mike -
Couple of things you should be aware of. Effectiveness of an attic installation is difficult to predict. There are too many unknowns, in the material of the roof and structure, trees and buildings and other obstructions on the other side of the roof, and conductive and/or noisy wires, pipes, chimneys, etc. that are part of the building. Antennas are designed to function in free air, and you can change their electrical characteristics by placing them in other environments. Some building materials are more transparent to signals than others. Stucco, for example, contains wire mesh typically and is basically opaque to TV signals.
So did your antenna work in the attic location? Certainly I would test that before proceeding. An "attic antenna" is just a cheapened outdoor antenna - not weather proof. There's no way to design an antenna specifically for attic use that's different from outdoor use, other than you can make is flimsier. So consider whether you are getting good value from the GE antenna, compared to, say, an RCA ANT751.
http://www.amazon.com/RCA-ANT751-Dur.../dp/B0024R4B5C - which also should be available from Walmart.
If the attic space is not terrible for signal, I think your main issue will be getting sufficient VHF-high reception. You probably want WNCT 10 and WCTI 12, which are pretty strong at your location and not too far separated at your locale. The VHF signal wavelength is long, and typically needs a large antenna for good reception. Bowtie arrays, which will likely fit in your space pretty well, are typically UHF only - ie
https://www.antennasdirect.com/store...v-antenna.html Your typical VHF antenna is a yagi design, and is long. The Antennacraft Y5713 and Y10713 are often recommended here
http://www.antennacraft.net/Antennas/AntennasVHF.html for combination with a UHF-only antenna. The Clearstream 5 is an alternative to something like the 5' long Y5713
https://www.antennasdirect.com/store/vhf.html but at a considerable premium. And you'd have to site it and your UHF antenna in your attic space.
The good think is you have quite a lot of signal in the air for that group of majors to the southwest, and they aren't too widely separated geographically. So you might be able to do it ...