Looks like the Koni STR.T's are expected to be back in stock by July 24th or 25th. I know we ordered more of these quite a while ago, but every time the start of a new race season hits, Koni goes through a tone of inventory. It usually takes a few months for them to re-up on with everything. I'm sorry for the long wait, unfortunately our hand are tied on this one.
There's a few things you're going to need to match your old Saleen. To keep a smooth and comfortable ride, I suggest using the SR Performance springs
. They handle well and drop the ride height 1.5" all the way around. Next you'll want struts/shocks
like the Koni STR.T's for max comfort and handling. Lastly, you'll need an adjustable panhard bar
to recenter the rear axle.
Camber plates or bolts usually aren't necessary for a 1.5" drop on 11-14 Mustangs. Also, there's a few other components that will increase handling and traction, but the parts above are the bare minimum and will get the job done without consequence.
I don't want to take the OP's thread too far off track, so if you have more questions, feel free to PM me directly. I'd be happy to help you out!