No need to carry a physical copy of your license around. You literally print it from home so no random person outside the FCC is really going to know what it is or think it's actually official. If some rando does ask to see your license, they have zero legal authority, so tell them to pound sand. If you do run into an FCC field agent(not gonna happen), they know they can instantly look you up in the ULS to verify your license is legit.
I would print out labels with your call sign though and put them on the fronts of all your radios for a while to help you remember it/remind you to use it. As u/CC878CO said, at the beginning or end of a conversation, or at 15 minute intervals if they get long winded, is all you legally need. Repeater owners may require more.
As for grounding, the set screws on the lip mount should be plenty. To be sure, hook a test light up to battery + and check for ground on the large part of the NMO mount(without the coax connected to the radio). A solid ground on the radio itself is usually a bigger issue.
You also don't need such a long antenna. GMRS frequencies operate with a wavelength of around 65cm(25in) and an antenna longer than that doesn't really have any advantages unless it's a dipole. The Ghost antenna should work fine both on and off road. I run a 1/4 wave NMO on the roof of my Taco because it's less likely to get snagged off road and I have no issues with range. It also doesn't scream 'potentially expensive radio to steal'.
You can tune the longer antenna by loosening the set screw and changing its length, or if need be even removing the whip and trimming some material from its bottom. The Ghost antenna, not so much.
Lastly, you probably don't need ferrite beads if your power & ground are connected/routed properly. The big interference sources, mainly your alternator, are much better than they were 30+ years ago because manufacturers now need to keep electrical noise from screwing with all manner of sensor. That said, I still run them out of habit because they are cheap insurance.
I use this on my cb350 and works excellent: Engine Timing Light with Spark Plug Tester,Inductive Timing Light Gun Timing Light Ignition Testers Engine Ignition Coil Tester for Car Motor Motorbike Vehicle Motorcycle Marine Lawnmower https://www.amazon.com/dp/B07NRNPR6H/ref=cm_sw_r_cp_api_glt_fabc_WDK4K7HRY5KHSEPKHH05?_encoding=UTF8&psc=1
Any 12v auto probe will work but I use this one. I cut the clamp off though so I could ground it easier: Heavy Duty Automotive Circuit Tester, Premium 6-24V Test Light with Extended Spring Test Leads & Sharp Piercing Probe, Circuit Voltage Tester with Replacement Indicator Light for Car/Vehicles https://www.amazon.com/dp/B07Q3622FT/ref=cm_sw_r_cp_api_glt_fabc_Y1TKSZZ9J0S3XBCG3HMT?_encoding=UTF8&psc=1