for TR2-6, get the type Moss sells. Either buy thiers, one just like it, or study the picture and fabricate one. (plate steel and threaded rod) It's gotta reach down through the center. anything that clamps onto the outside dosen't work.
The way the frame wraps around part of the spring (especially at the top) any attempt to hook up an outside type one causes the spring to compress in an arc, and then it's durn near impossible to re-fit.