Keb, hoping the mattress is sitting on a full-size plank now and not slats that might typically hold up a box spring? Otherwise you could end up with saggy points. If you decide you want the mattress to be less firm you could add one of those eggcrate toppers (they come with many thickness and firmness options). I have one on my mattress (because the mattress wasn't firm enough but the topper helped.)

Why don't you offer the box springs on a buy nothing or Freecycle page? Then they'll come pick it up at no cost to you. I am a moderator on a local Freecycle page, it's pretty straightforward and there are few complaints (mostly if someone tries to offer things for sale instead of free). I'm less big on the Buy Nothing group because it uses a phone app that I'm not interested in, or on Facebook, that I don't think you use, and they're very picky about the boundaries of the area they serve. Not a group in your area? They ask you to set one up - nope. A bonus to the Freecycle group: I've made several friends in the last few years through those pages.

My son and his partner have had a bug for a few days and realized their COVID tests were expired, so are getting more. I looked through my tests here and all are expired, one is marginally useable if needed soon. I've disassembled the boxes for recycling or trash and ordered (for a cost) a box of COVID and flu tests. The federal FDA COVID site is awash with trash and conspiracy theories now and an outright libelous account about Dr. Fauci. "Cleanup on aisle 47."