Maxxair vent cover hinges frozen

[Triton]

The Maxxair vent covers on our 2007 Journey are frozen and I can't seem to get them loose so I can open the cover and clean/seal around the vents.
There are two on the unhinged side that secure with a small perhaps one inch carriage bole with a wingnut up top. The carriage bolt must not have the square head to hold it in place as when I turn the wingnut the bolt turns as well. I've sprayed them with a small shot of WD-40 and tried to put pressure on the bolt head with a wooden shim and flat heat screwdriver but it still turns. Bolt is not long enough, nor is there room to get a grip on it with a vise grip.

I'm looking for some advice on how I can get these open. Once open I can see replacement hardware kits available but I have to get there first......

[Triton]

Really hoping to get some advice on this string.... Surely I'm not the only one who has or had issues getting the cover to swing open?

[Morich]

DIY often involves making things work even if we have to make it up as we go! Much of it depends on tools on hand!

When looking at a bolt that I can't hold in any other way, I assume it has to be cut out and I reach for a "Dremel- type" tool to cut it off.

As an alternate thought without knowing it would work for your case, is there a chance you could use a small tube and flood the hinge to loosen it up.
I use a fair amount of this stuff:
https://www.homedepot.com/p/Blaster-...E&gclsrc=aw.ds

Get one of the types with a tube nozzle, extend it with some small tubing like a straw, etc. to get it far enough in?
Pour a bunch on, wait an hour or so and then gently try to work it?

Maybe hold the mouth just right to make it work?

[Triton]

LOL. Roger that. Thanks for the prompt reply.
I had been thinking I may just have to try to cut it off.
I'm not (yet) and owner of a Dremel (odd, I know) but I may be able to get my small half size hack saw in there for some back and forth forever action.
Kidding.... I think the son in law may have one I can borrow right away.

I'll give it another shot when the climate outside is mild enough for me to wander up there.

Thanks again for the advice.