Hey all,
just did something interesting. I bought on Temu a portable washing Machine 11L. It ended up being about $10 w a discount.

I thought carpet cleaner would be best, it has sort of a slick finish when drying. Use Bissell - its $$ but works awesome!
I wan it on each belt for 7 or 8 mins -and extracted a TON of nastiness.

Just dont pop the drain plug and leak all over your seat!
I'll report back after they dry as well.