Thank you all for your input, very much appreciated. Right now, std spring rates, the car will be driven somewhat hard on the street. Some 1/4 mile runs once in a while. Our roads out here are horible, I had an A body years back, very low ride hight, I had great success with Koni as I could adjust the rebound, once set to what I liked I then just left it, but, the ability to do this was night and day in how the car handled and it almost removed all bottoming out on nasty roads.
Id like to be able to easily adjust the rebound on and off, Koni you have to undo the top of the shock, compress it and rotate it to adjust, the QA1's single adjust has at least the knob to adjust externaly etc,
I may increase TB diam pending, oh, its a 73 Cuda 340, so not being a BB helps.
right now, Koni are available out here, everything else is ex US, to rebuild others will mean shipping back to the US,,, just more $$$.
Greg