You can cut rear springs. It is best to use a set of cargo springs, though. When you are done, cover the cut end with fuel line hose to give it something to rest on and put it on top in the perch. Just be careful to get it in nicely in the perch. The reason it is best to use cargo coils is because the coils on that end are close together and give a more firm/reliable end to sit in the perch.
Granted, it won't have the pig tail end on it anymore, but it works with the fuel line hose to help keep it seated.
I have it in my el camino and I am sure others have done it as well.