so i finally picked up a used FT-7900R to replace the old 2300H that died on me last spring. got it mounted under the dash on the passenger side which feels pretty solid, but im running into the same headache i always do with coax routing. right now i just ran it through the door jamb rubber seal which i know isnt ideal but it was getting dark and i wanted to get on the air.

the antenna is a NMO mount on the roof center, so the coax has to come down the A pillar somewhere. has anyone run it inside the headliner on a full size truck? i have a 2018 F150 and im a little nervous about pulling that headliner down, seems like a lot of clips that like to break. or is the door jamb actually fine long term if i'm careful about it? the coax is LMR-240 so its not super stiff but not floppy either.

also curious if anyone has had issues with the 7900 picking up noise from the alternator on these newer trucks. read some horror stories about the F150's electrical system being a nightmare for RF.

i did the headliner route on my 2017 F150 about two years ago and honestly it wasnt as bad as i expected. maybe 6 or 7 clips came loose and i only broke one, which i replaced for like a dollar at the ford dealer. the A pillar trim just pops off if you work it slow from the bottom up, theres a clip near the top that can be stubborn. i ran RG-8X and left a little service loop behind the dash and havent had any issues since.

the door jamb thing works for a while but ive seen it chafe through the jacket after a year or two of the door opening and closing, especially in winter when everything gets stiff. not worth the risk of a short or water getting in.

as for alternator noise, i did need a ferrite choke on the power leads and also ended up putting one on the mic cable. the newer ecoboost engines seem worse about it than the old 5.4s in my experience. worth checking your ground too, i grounded mine directly to the chassis with 12 gauge and it cleaned up a lot.

just wanted to chime in because i have the same radio in a different vehicle but the alternator noise thing hit me hard when i first installed it. took me forever to figure out it wasnt the radio at all, it was a ground loop from the way i had the power run. once i went directly to the battery with proper gauge wire and a dedicated chassis ground point it got way quieter. still get a tiny bit of whine on 70cm if i crank the audio but 2m is totally clean now.