Ok, tried most springs in tester and come to the conclusion that Rip-Off is the word.Two makes(well known) were purely cut down standards, one looked as though they has been half cut then snapped. Put six different springs on a home made tester calibrated with a known 2.25 in x300lb spring,nothing came near, either to advertised rate or suitable rate.So nuts to that, am going to make my own.Problem,2.25 in springs and thread tube will not fit over 56mm OD leg. Next plan is to put the leg tube in a CNC lathe and machine a thread down the leg in order to fit then I can make my own set up.2.25 springs in 10" or 12" length are $38 here so can afford to experiment,the question for the experts is: anybody done this before, and is there a better way?????????????!!!!!!!!!!!!!!!!!!!!!