Clat trac vs. SS springs vs 4 link

73' Duster, 360 (450hp?)/727 reverse valve body. 8 3/4 posi w/4.10's, minimal interior, sub frame added and adding 10 pt cage. Battery in trunk. What's the best SS spring for me? I have a set of #3000 springs hope that will work. I dont want to relocate the springs just yet, I'll plan that for another time. Any Comments?.. Good or bad are taken..

Thanks, Eric