Basic springcompressors should work fine...or is it any other issues you are having ?
There may not be enough weight to make it work with a jack. A piece of pipe between the frame and an I beam above. if you have that available might work. Coil springs hae a lot of potential energy when compressed. It can be one of the more dangerous things to work on.
Standard operating procedure to remove and replace the spring is to put the weight of the car on the spring (compressing it) Disconnect the upper spindle support bolt, then lower the 'A' arm and remove the spring.With no weight on the chassis I don't think jacking the lower A arm will work. I would use a heavy threaded rod (1/2" or larger) through the shock absorber mount holes on the frame and lower A arm to compress the spring from the inside.