Gdub
330mm really? That is higher than a standard GL! Are you sure you have them seated properly? something is definitely not right there is they are a so called 'low' spring
the free length of the springs is irrelevant to the height in the car as you could have 2 springs that are the same length but totally different spring rate which means one will compress further with the weight of the car on it than the other
They've been in the car for about 30 years so if they aren't seated correctly now, they never will be! Seriously though, I wouldn't say they are higher than a standard GL; I remember it being about standard or just marginally lower. I have standard height tyres and rims on, and there's about an 5 cms between the top of the tyre and the bottom of the guard. As that's the about the same as I have at the rear, it doesn't look ridiculous at least.
Yes, I"m aware that free length isn't the only consideration; I listed it just as a point of reference for others seeing I had them handy, as springs with a higher rate than standard would definitely have to be shorter overall to qualify as "lowered". Maybe I'm getting soft in my old age but I might even put the original springs back in for the sake of improving comfort seeing it is just a street car. If I do I'll post up the difference in height.