The rear suspension is an 3 link with an underslung watts. I love the lightweight and simplicity of this watts, no giant cantilevered brackets hanging off the rear housing. However it is not adjustable, I use the rear sway bar and springs to tune. A low rear RC is highly recommended by Mark Ortiz and other live axle racers, and this is about as low as you can go. I just reinforced and gusseted the housing and pierced it with some threaded rod, also gusseted inside the housing, then added a double shear bracket out of .125 steel. I forget the name of the guy who made my "football" it was kind of a one off deal. In the photo a few things are mismatched, that is a very old photo that was still using mockup pieces.
Oh here I did find the rear caliper mounted, not a good photo as the light doesn't really catch it and you can't really tell how large that caliper really is, plus my older equipment is kind of dirty not like the real sexy build photos of all new parts we're used to seeing here.
Note that the link and swaybar and caliper brackets are all bolt on not weldon. I use anti-rotation bolts and I've never had a problem. Heckuva a lot easier than welding them.
The links for the 3 link are 29" long, and use Howe rubber bushings up front.
It is a full floater of course, but without some of the fancy hubs and hardware that have been showing upfor PT cars in the last year. But again, big beefy circle track hubs and direct mount hat with floating 14" rotors. Aluminum 3rd member case (10 lbs lighter). Trutrac diff with 3.08 gears, 31 spline axles.
I think my Anti-squat percentage is only about 50%, but I'm still not convinced you want greater than that or not for road racing. Never had a problem with brake hop !
I am running 250 lb springs for a wheel rate of about 275 lbs with a 1.1 motion ratio.