On a side note, anyone have tips on removing upchucked stomach contents from the dash crevices of a Jeep Cherokee? Yes, todays Christmas travel has been exciting.
Isn't that what car detailers are for?
If you are talking about the corners and such-like, then toothbrushes and cotton swabs are your friends. If you are talking about ventilation tubes and other places where the bottom is far away, then you really need to pull everything and wash it out with something that will kill both the upchuck and any bacteria/mold/virus already growing there that might feed on the new food source. Given how much work is involved, paying a detailer who provides some sort of warranty for their work is a reasonable investment.
If you don't want to pay a detailer, go to your local farm store and buy a 5-gallon pail of the deodorizer used for hog pens and liberally pour that down the crevices. Lather, rinse, repeat until you are not gagging every time you turn on the heat or AC - which is how you test to see if you have gotten rid of it all.
stay safe.