In a message dated 6/17/2016 12:48:11 P.M. Eastern Daylight Time,
vidublu@GMAIL.COM writes:

I was  just eyeing those to flat head bolts on the bottom of my rear 'shelf'
that  houses the A/C.  Sounds like those are for support but I wondered,  is
there not a filter somewhere on the A/C system that I should  clean?  I'm
thinking after 26 years it's  due.

its just a thin piece of foam that's wrapped around the cooling  fins..
you can probably use any thin filter foam like  that