Hi
I mounted mine on the rear roll bar, routed the cable into the cabin by floor grommet located rear of front seats in the floor panel.
Check https://buya2wayradio.com.au/antennas/brackets/RFI-BK-900-ADJUSTABLE-BONNET-BOOT-MOUNT
Used a RFI mount with a short 3db aerial works a treat.
Hope this helps.