Get the Steeda full length units, they come with plates that go on first, then the subframes themselves. One of the few times I will not recommend MM first for a suspension part although the MM ones are just as nice, just sans plates.
. Provided you have a 79-04 of course...
2000 Mustang GT Steeda #0048 34k miles. 99 Cobra 4V swapped, FTBR IRS swapped, exhaust, tuned by James Gordon.
Just because I give you advice, doesn't mean I know more than you. Its just means I've done more stupid ****.