If you cannot get the stock spring back in there, you could try leaving the strut mounted to the LCA but disconnect the two bolts from the LCA to the K. The LCA will pivot on the strut. This gives you a ton of room for a tall spring. You have to be careful when doing this (a big, good floor jack is a must). If interested in this method, read up on it and be aware of all safety concerns before attempting it.
Good luck.