Safest way?

[SLR_dave]

Actually : Postnote.

I just googled fo th 3A15 and its been out of sight for years, what was I thinking?

But the solution is simple, theres a thread on it on the Old Holden site. You just make your own compressor tool out of threaded rod and lock nuts, if you arange the shape of the lower plate/arm with considered creativity this should work well, I'd use a nice thick spacer washer (or two) for the top of the shock tower. I wouldnt use spring steel for the lower arm though, but def go 5/8' on the rod.
Remember that becuase the coils of the spring are spiral, one side of the lower arm/plate will need to be be higher than the other to get tension on two sides of the spring, ie; it will want to sit on a diagonal, or be shaped with one end higher than the other and perhaps a curl or bend or etc to hold the coil on each side .

http://oldholden.com/node/55828