Well I guess it depends on what you want from the car. Looks? Performance? How serious on the performance side?
You do not need a 4 link and a coil over front end to perform well. Here is an example of a '71 Challenger (same chassis as your car) with modifications to the stock suspension that does pretty well for itself:
http://www.hotrod.com/cars/featured/...legal-racecar/
If you are trying to be nationally competitive in the "Pro Touring" events, then that is a different matter entirely.
My car is yet to be on the road, but I have essentially a modified version of the stock suspension with relocated rear springs. The car will handle reasonably well and will fit a 275-35/18 front and will easily fit a 325/30-19 in the rear. My car is smaller than yours but is basically the same suspension. And, I have seen E-body cars with as big as 315s on the front.