Spring compression tool? What for? Grab a couple of C-clamps to hold the sheaves together, remove the three nuts holding the helix in place, GRAB the helix with your hands (you can use leather gloves to hold it if you're not comfortable twisting against the spring), turn the helix CLOCKWISE to remove sideways tension, and pull off. Before you completely remove everything, make note of which holes the spring sits in. Assembly is the reverse.
Oh yeah... one thing to note: It is MUCH easier to work on the secondary clutch while it is still bolted onto the jackshaft with the e-brake set.
Once the helix is off, remove the bolt holding the clutch onto the jackshaft and remove.