The original Merc suspension isn't much to write home about. I built a steel Merc a number of years back and used the front of the frame and all the suspension off a mid 80's Crown Vic cop car. I have a 'glass Merc I'm doing now that is on an '83 Crown Vic chassis and I've built full frames for a couple other Mercs. There are some pics in my gallery if you're interested. My email addy is in my profile if you want to discuss specifics.