left and right front springs question ?

hi fitting a new set of front springs (slightly used ,no instructions)
and noticed a bit too late that they are marked left and right.
no prob to swap them out but .......i am in australia where we drive on the wrong side of the road and the car is still left hand drive
so any one know why they would be left and right ?
if it is to counter the weight of the driver then i have done the right thing

if its to do with the camber of the road i am gonna need a lot of adjusting shims ! but i cant see how springs would hold camber or caster for long and they are correct for the car which uses shims
any thoughts ?

 

rang the spring co today and i have done the right thing .the slightly higher rate is for the drivers side (wherever you may be )
interesting to note one inch lower than stock is actually higher than the old saggy springs on the car . i will bash round a bit to see if they settle !