I,ve been meaning to do this for a while! I sent my local agent a sample of a 1977 504 wagon ( 2litre petrol , 4 speed manual) front and rear springs. They have requested King springs to re-produce them for me. The rear of a wagon has 4 springs, and the fronts are stiffer than a petrol sedan. When I did the Canning Stock route,in my 505, I had a set of the wagon fronts fitted in the front to lift it a little! the set up, worked well. It will take them a few weeks now, but once they re-produce them, they should have the spec's in there system. Anyone interested? cheers Andy