Some guys use a porta power between the eyes. I have a spring spreader that my dad used on Model A's that I have never even used. I'm always taking the springs completely apart anyway to paint the individual leafs. There is not a great deal of tension on a leaf spring like there is a coil spring, I worked on a 400-vehicle fleet for 30-years. I replaced a lot of individual broken leaf's that required removing the center bolt. We just used two large "C" clamps to hold it all together and then removed the center bolt. Even one clamp would work on a Model A. Pull the rearend out with the spring on it, use a large "Clamp that will be long enough to relieve the pressure as the clamp opens up. I better tell you to use two just to be safe.
You describe how I "ended" my spring removal described above beginning with the "water buckets" - and ending up with the loose but assembled spring on my workbench.
At the point of disassembly for blasting/painting.
Clamped in a workbench vise hump up with the center bolt pointed "up." And a LARGE (single) C-clamp holding and waiting for the center bolt to be removed.
So with the spring in my mind fully restrained by the large C-clamp I go ahead and cut the center bolt. Now mind you this is the 82A truck spring, which is the "stoutest" spring of the Ford Model A spring circus. I cut fully expecting no real reaction from the spring since the clamp is holding it.
Cut done -head falls off. I reach for a large punch to drive the center bolt "down" so it falls on the floor. Two swipes with the hammer/punch and the clamp/spring decides to "squirm" since the bolt is now 2/3rds removed.
UPWARD launched from the vise the upper 2/3rds of the spring - miss me and bang hard against the dining room floor above - and fall in a rain of steel around me.
My mother calls down from the kitchen above - "What happened - are you all right?"
Fortunately I missed all of the excitement (and impact) in BOTH accelerations.
"Fine Mom."
Damned fortunate. It would have been a real good way to break an arm - or worse.
And YES - use TWO large C-clamps - possibly even two smaller but stout "bridge clamps" (four all-thread rods) - and replace the center bolt with some Grade 8 allthread bolt about 18" long - and only then relieve the pressure on the spring "equally" beginning at the center bolt.
The clamps only serve to give you time to insert the all-thread.
And then go back together as described above.
I have described this story before I believe - Others describe the lesser Ford Model A springs as more forgiving. But you can never be sure.
Just be careful out there.
Joe K