Coil springs

My son and I are in the middle of fixing up his 56 Apache. We started out
by putting in a 350 w/a 400 turbo and a 69 Nova's rear end. This combination ran
too darned good for the truck's own good, even with a brake booster it just
didn't want to stop, plus the young man just didn't like the big ole steering
wheel so power steering was the next idea.  So we cut the front end off of a 69 Nova SS and a welder buddy of mine helped us "fish-plate" the 69 Nova front end inside the frame rails of the 56. Now I know the old truck is going to weigh a bit more than the Nova, so any ideas on which coil spring would fit in a 69 Nova SS front end to get his 56 handling half right?
     Thanks for your ideas, might save us some time.

     Oh, and for all of the guys wondering about why we would mess up a 56 Apache, well that was done in Virginia. Seems the 56's frame was shot by setting in a field in Georgia, and to get it legal in VA. they found a 59 frame, and VA registered the vehicle by that frame #. So Antique value not what you are thinkin.  

I would contact a spring retailer with info about the truck and see if they can come up with a match. The chances that someone here has done the same swap could be slim. Welcome to the forum though.  
Jim
70 El Camino
461 solid, m20,
pics in readers rides