Radio's...May be a stupid question but.......

May be a stupid question but.....

As some of you know, i'm putting a CB into the Defender and getting that hopefully sorted in the next few days. However, there are times, that for work and also other bits and pieces that we use UHF GP340 Radio's....

I spoke to a chap at work today who suggested that this mobile motorola radio GM350 :

which is effectively a taxi radio, will work with the UHF GP340 hand helds we use at work.. it would just be really nice to have a fixed unit in the cab of the landy as well as my CB

However - this is my question...
As most of the mobile units that would be permanently installed would run off a ''mag mount'' type aerial which you wack on the roof - and being the Defender that's a no go - can i use the same aerial as the fixed springer aerial that's being installed on the back of the 90 this week?

Can two things ( CB and mobile walkie talkie ) run off the same aerial?

This may be an absolutely stupid question - in which case, i'm prepared - but i just want to know if it's possible as i really don't know anything about them, other than i need two units to contact the people i need too ( CB and mobile walkie talkie base unit in the car )

Thanks for any advice or help as always and sorry if it's a stupid question in advance!

If i can latch on to this thread (if OP doesn't mind!) as i have a few radio questions. Is there something better than CB (and by better i mean longer range) that one can use. What do the military use? Surely they cant be CB radios (can you tell the level of ignorance here!) Is that sort of thing available - i often see the Clansman set ups for sale - could those be used?

Old chap I used to work with had a radio on his hi vis which radioed back to his antenna on the roof of his van which signalled back to his massive antenna on his mast at home, I'm guessing just like a taxi company would use. I know no details of it except for that as he used to speak to his Mrs miles away for free.. I personally have unlimited minutes on my phone but each to their own. Regarding same ariel then I'm sure his ariel at home on the mast does all frequencies Im sure it's down to the equipment so I couldn't see why not