I will probably bury mine and if anyone asks claim they were stolen a long time ago.
I've heard it said that when it's time to bury the guns, it's then time to dig them back up and load 'em.
I also suspect that a mission critical approach to final gun confiscation will be to nab/arrest/kill/disappear all the folks that DID disappear up into the hills, as they definitely have fighting spirit. And initially they would be isolated when they "run for the hills." No big firefights, just lone reactionaries who are stranded against superior forces. DEA/FBI/ATF/LocalPD/DHS/NG swat-like teams would take out each and every isolated person/group.
The only protection is immediate armed rally, when such a move is made by the federal government. If a group of 100+ people can form quickly enough that they aren't arrested as kooks when they only number less than 10, that is the heart of your revolution. The weaponry of those 100+ people needs to be able to out-gun anything the locals can throw up, so it needs to be a mix of AR's/AK's/SKS's/M14's/FAL's and long distance weaponry such as .338 and 50BMG rifles. Around here, sherriff Joe Arpaio has an APC with an M60 mounted up top and I suspect he would fall in with the gun grabbers, so AP rounds are critical.
Look to your large community shooting centers. In Phoenix, Arizona, I would expect Ben Avery Shooting Center, Usery Pass shooting range, Caswell's gun club and Scottsdale gun club to be rally centers, along with the more popular gun shops and gun accessory shops such as Dillon Precision. These are politically active sites that have wealthy and influential gun owners that are members or owners.
Similar community shooting centers exist in other cities. I would expect resistance to begin near these as gun owners rally to one another for support, information and protection.
Another place to look would be National Guard armories, although I expect they would 90% or more go to the federal side. Any guardsmen not siding with the .gov would simply not show up on base. I suspect that most will place their allegiance in orders rather than oaths, though, and the armories will thus be under government control.