Here you can see the driver's side 2-meter antenna mounted, same approximate position as the standard radio mount, just opposite side for symmetry. (a slight bend makes for an upright presentation) Holes/cutouts under the hood (inside the engine bay) allow you to install the antenna without additional cutting - only one drilled hole required to mount. this antenna is about the height of my rooftop. (i do have a magnet mount 5/8 for the roof when needed - about 1% of the time for me.)
antenna placement is NOT critical for reception; the perfect placement for transmission is the center of the roof/top. However, you may not want to take the antenna off and on every time you enter or exit a garage or drive thru... which is why I have a shortie on the driver side. All this works fine for an antenna for 2-meters. If you are on the higher frequencies, the antenna is so short you can roof mount and probably not even remove for your home garage (test that first before you commit to drilling the hole). For HF, which requires a much taller antenna, a receiver/hitch mount is best because you can more easily remove it and it does not bump everything you drive under.
Here is the 2-meter rig mounted in the center console. i leave the lid screws off to make the console top removable - i just set it aside when operating the rig. The radio mount is attached to the passenger side of the console interior side panel. remote speaker plug and antenna feed from holes in the bottom of the console. You will need to remove the console to run speaker wires, power cable and antenna cable, drill holes in the console and attach the radio mount. (when complete as above, the radio is easily removed with the two side hand screws as if mounted under a dash). out of sight is always better - just remember to turn the rig off to prevent battery drain. remember, Ham radios need power and ground to the battery - remember to fuse BOTH positive and negative feeds (do NOT use the cig lighter wire/fuse). also, use correct gauge wire for your full transmit power.
the speaker hole pattern is already on my 1987 fj60. when you remove the glove box interior, you can easily mount a speaker (can't remember the size now), and then run the wire to your console for a remote speaker that you can easily hear!!!
this is handy for NOAA weather reports, monitoring other frequencies or talking to another ham; the volume is so much better and the sound quality is so much better!
If you are in a more remote location and need every bit of antenna gain, only consider the center roof mount and watch what you drive under!!!