There are good reasons why the default answer is to fit telescopics.
- The lever arm system was only used on the Vitesse Mk2, so parts are not easy to find, either the dampers or the drop links. The dampers are probably used on other vehicles (don't know what) and a rebuildable so the biggest problem is the drop links, especially that top rubber-filled ball joint.
- The lever arm system doesn't work very well - less effective than telescopics. It still remember the huge improvement in rear end behaviour that came from fitting plain ordinary Armstrong telescopics on my Vitesse.
- Fitting telescopics gives some choice of damper makes and the possibility of fitting adjustable ones.
- Fitting telescopics is pretty straightforward. There are chassis extension kits available from various places and if you've converted to CV shafts you can use the standard (for non-rotor cars) chassis mounting position anyway.
If you want to stick with the lever arm dampers, fair enough. Shouldn't be too hard to engineer a nice solution. Quite a few modern cars use nice ball joints (like small track-rod ends) and you can buy these http://www.racingbeateurope.co.....nd-linksb-1863-p.asp
for MX-5 which implies that you can buy the joints themselves seperately.