Advice on how to approach swinging with husband

I (34f) have fantasized about my husband (37m) and I sharing the bed with another woman or man or preferably both for quite some time. I’ve been married to my husband for 8 years, been together for a little longer than that even.

The desire began several years ago on a group trip to a Gatlinburg cabin with a few other couples. One night, my husband and I along with one of the other couples stayed up until 3 in the morning drinking and hanging out in the hot tub while the other 2 couples went to bed. Toward the end of the night I was making out with my husband and getting handsy and so was the other couple. We laughed about it when we both noticed and decided we all needed to go to bed. So nothing crazy happened… but that moment planted the seed. Recently I brought it up to my husband casually that “we should do another trip to TN with everyone, that was fun” and he said “yeah that would be cool”… and that’s where I’m at. How do I approach him about this desire?

Our sex life is still good, so I don’t want to ruin that. We aren’t incredibly vanilla either, we role play and use gadgets to keep things fun lol. How can I know he would be ok with swinging without telling him that I am? I think if I knew beforehand that he would be ok with it, it would be much less scary to bring up. Any advice would be helpful, thanks!