the suspension pictured is the 1975 Direct Connection Duster Butch Leal raced in NHRA modified production (M/P). The rules required OEM front and rear suspension (leaf springs) and allowed traction / ladder bars.
That is a sneaky way to do a link suspension! Just use the "stock" springs instead of coil overs.
In a three link or four bar the gain you get over the ladder bar style shown is the ability to change the location of instant center. The instant center is the imaginary point that the axle pivots around. Easiest to understand in a ladder bar or truck arm because it is the actual pivot point where the front of the ladder bar mounts. In a four link you adjust the upper and lower arms to move that pivot point forward for less bite, rearward for more bite. The Pro Gas / Super Gas car I used to help out on 30+ years ago we would paint shoe polish on the wheelie bars and adjust the "bite" until we were barely using them or not putting enough pressure on the wheels to clean off the polish. The idea was to get all the weight on the rear tires but not waste energy picking the front of the car up more than necessary. Also a good idea to get left right dialed in for it to launch straight since the front wheels were not really capable of steering the car!