Should do it properly, but I ran for years on cut springs without a prob. after I sold it, it was roadworthied with them twice!!!! Hell I had them help in with zip ties to stop them dropping out :jamie: Ran GT Gas Monroes (?) of the standard length.
If you have access to a hydrolic press, reset the rears yourself. Did it to mine, lowered the main leaf by 2" out of the car. Dropped about 3" when back in the car, just off the bump stops (13" tyres were inside the rear guards ). Again standard length GT Gas Monroes were used with no probs after I found that a rear shock mount was bent and breaking off the bottom of a shock.
Could also use Commodore wagon (VK ish) or HK/T/G Monaro rear shocks as they may be a bees shorter.