yes, you could probably fit 22's with a very low profile tire without having to worry too much about rubbing the fender wells
No. it will not fit.
no
no
No. depending on your model, it fits 1997-1999 deville, 1995-2002 eldorado, or 1992-1997 seville.
yes.
yes
No the engines are not the same.
No.
1992-2002, comparable Seville models should work also as they shared the same platform.
Yes it will fit
yes they can you can put them on without lifting and they will not rub
Yes/ No but with alterations and shared parts.