can't really help you with your question. i suppose that they are different length, as many people with 4x4 cossie have changed to other 4x4 ones (so the opposite of what you want to do).

nce car, i have one too. i just junked the v6 and transmission and have rebuilt 2wd cossie running gear into it. there's a thread in the projects section if you're interested

https://passionford.com/forum/viewtopic.php?t=132709

bw, did you get a complete spring kit from spax? i need harder and shorter rear springs, but can't find them listed anywhere for the back of an estate (the spring diameter is bigger than saloon).