Well - nothing great or fancy, but here's how I do it...
Actually, I have this same setup in the '02 Dodge/Cummins we use to pull our 5th wheel:
BUT, I'm getting off topic for this thread - deciding to install my second Icom 706 MKIIG in the '88 Winnie we bought last year for for towing our boat on fishing expeditions, I started out selecting a suitable out-of-the-way spot below the dash on a vertical surface housing various electrical control devices and circuits - I wanted the main 706 box install to be quickly and easily removable, so fabricated "J" style hangers to engage the slots on the 706 mobile bracket:
Here's the 706 installed on the mounting "hooks":
It's quite solid, and secure - yet quickly easily removable. Here's what can be seen once the lower dashboard valance is put back in place:
And even that is not nearly as visible from other angles from inside the MH.
Here's the bracket I fabbed up to mount the 706 faceplate:
Secured to the underside of the dashboard "lip" with clear silicon sealant - quite sturdy - and no holes drilled.
Here's the 706 faceplate mounted and installation completed:
Pretty unobtrusive or invasive - yet quite easily used either down the road, or at destination. In the truck installation, I also run an Ameritron ALS-500 solid state amp - the extra power is very helpful in mobile situations, and along with the very efficient and heavy-duty antenna I designed and built for 40/20 meter operation, gives contacts quite similar to those from my home QTH.
I plan to install a remoted Yaesu FL-2100B linear amp in this MH, down in one of the basement compartments - it can be powered by the MH's 4KW genset in motion - or shore power, and will deliver a solid 700-800 watts output. BUT, will cover that and mobile antenna used for higher power mobile apps, in another thread.
NO, not everyone can duplicate this install - or would even want too - but it might give other hams a few ideas as to rigs to use, or methods of installation - I dearly love my 2 IC-706MKIIG's - they are so compact, and extremely versatile with their remote faceplate capabilities. On my 2 mobile rigs, I also use the Clear Speech interference eliminating speakers - in both my mobile setups, there is near total absence of any interference, a definite plus in operating.