Air cleaner ideas?

I certainly would not start with a nice unit if I was going to attempt it for the same reason. Someone might need a nice one, so why ruin it. The one I found has already had the snorkels cut off, but after looking at it, I don't think that I could do a good enough job to be happy with the finished product. So, now I am considering my last two options, as well as adding something like yours to the list.
Sounds like the one you have would be perfect to do the conversion on.