I think this may work I need to check the thickness, as this one is only good out to 1/8" and I may have to bore out the opening to accommodate 3/4".
This Laird Antenex 3/4 Thru-Hole NMO Mount is optimized for vehicular roof mounting of an NMO type antenna. Typically used with VHF or UHF or high-frequency (900 mhz+) antennas, the NMOHPCNRPSMM518 includes a 17 Ft. ATX195 Cable and RP-SMA Male Connector Installed If this is not the NMO Mount...
www.arcantenna.com
My intent is to run signalstuff's new automotive antenna.
NOTE: To use this antenna you need an NMO mount. There are many different types and they are easy to find, so we don't carry them ourselves. (There isn't enough room in KD7BBC's garage to store them...)
signalstuff.com