[LEAKYSEALS951]

Depends on what you are trying to do.
Trying to keep the core clean? Trying to keep out pollen? Both?

I replaced the cabin filter on my car last night. Fun times. While I was watching a YT video on how to access the location, I couldn't help but balk a bit at the announcer...

You NEED to change your filter to keep out environmental toxins and unhealthy air.
"My god!?!?!?" I thought, how did people survive before cabin air filters became the norm? Should I put on my n95 mask? My 911 doesn't have a filter. Am I safe? Egads. the horror!

If you are trying to keep the core clean, since the truck/suv is already got some years on it, it's already got smutz in the system. If there was an easy way, I'd try to blow compressed air in reverse through the core.

Probably not feasible. Even if you were to make the access hole, and then clean the core from there, it might get at some of the debri/ dead squirrels.

Trying to keep out pollen/dust? Put in the filter and seal it best as possible. Some adhesive foam strips should fill in the gaps, and release formaldehyde to makeup for all the fresh air you'll now be breathing.
Good luck.