Tailgate lock problem

On my DC 2012 with bed cover, I use tailgate key lock few times a year, typically in winter, when we go for skiing and need to lock skis in bed. The problem is with the key hole of the tailgate lock - after winter driving(in Canada), the key hole get dirt, snow, ice and that chemical shit from the road treatment, which basically creates concrete inside the key hole and makes the lock unusable, can't even insert the key. That small latch in key hole usually helps but when I start to use the lock in winter, soon or later that latch gets stacked in open position and the dirt gets into the key hole. Last year (after few winter seasons), I replaced the cylinder lock (Simply Keys ...$20) and have tried it few days ago and it was already struggle to get that small key into lock. I assume there is no liquid that I would inject into the lock that would magically dissolve the concrete.

One way to get around this problem would be to install electrical lock which would work when the key lock becomes unusable (I looked so far into either Pop n Lock or Pace Edwards Powergate). I was also thinking to put a piece of duct tape over lock to cover it from dirt.

So, has anybody dealt with this problem?
Have you come across any handle that would actually be designed to cover the key hole? I would rather stay with key over going electrical.

 

I had a problem with my lock being dirty as well.

My key would still go in, but it would come out all black and nasty.

I ended up covering the key hole with a thin earth magnet that is the same size.

No more black crap.

edit: I cleaned out the key hole as best I could before I put the magnet on by putting the key in, pulling it out, and wiping it off.

 

magnet idea seems to be the best