.....kind of reminds me of the old story, you can have a quick repair, a good repair, or a cheap repair but you only get to pick two.
The hands down cheapest is: find a old Pinto that hasn't caught fire yet, drill out about 10,000 spot rivets in the cross-member, use 5 bolt Granada rotors and build some strut rod frame brackets. Did one 20 years ago on '46 other make truck, its now sold but it is still on the road.
I'm thinking the Crown Vic is too wide but it can be narrowed at some expense, a tread/track width measurement compared with whats available will help the decision. I'm using a Dakota sub-frame in my '56 at around 60 inch's (I think) wheel mount to wheel mount.
My '51 other make big block shop truck has a MII kit for 32 inch (?) frame width, works good. Some pictures available if required.