Im looking to mount an Austin Spectra mag mount on the roof of my house, or attic, not sure which one yet. However the NMO mount has a 17' lead of RG58 cable ending in a BNC male connector, and i have to extend this to about 75', but the RG58 extension cables over 12' are UHF males to BNC males. Do i have to use the RG58 cable all the way? Cant seem to find any adaptors that will make this work.