For best FM stereo
reception and range I used a coax switch and two short male-male coax cords to connect to the masthead VHF-FM antenna. Since FM is pretty much line of sight the higher location will pull in a lot more stations.
Have not read any tests on potential signal loss across a coax switch but subjectively do not see any difference in range on the
VHF. Just in case, the switch and cords are right next to the
VHF and it's less than a minute to unscrew the switch and connect the antenna back to the VHF directly.