240z/260z inserts. (Brands?)
So you dont have inserts yet? I know you can get tokico adjustables for 240zs for a pretty cheap price from the US, similar price to just normal pedders sports rider...but i'd say they would be a whole heap better shock
what governs how much you take out of the original leght? (front end has to come down about 105mm) and do you take out the additional 25mm for the bump steer spacers?
aslo at what height on the tube do you install the sleeve?
the length of teh new insert 100% governs how much you shorten the tube. get the new inserts, sit them in the strut. Measuer how much shorter they need to be, remember you have to allow for the nut at the top also
Take out an additional 25mm for bump steer spacers, which i assume are actually more roll centre adjusters than bump steer. And they go on the bottom of the strut between the strut and the steering arm and have no effect on the ride height
I'd personally have the adjuster on the coilover sleeves in the middle then sit them in maybe an inch down from the top of the strut, put one decent tack to hold them on place. put all the suspention together and see how it sits. If you have to lower the perch a heap to get the ride height you want, measure that distance and then lower the sleeve by that amount so that the adjuster is still in the centre
At the end of the day its not that important where it is as you can always get longer of shorter springs to suit