Good, I'm glad that my post might be useful. I have no idea about the sizes really. I didn't know what size my screw was and I Googled what size screws my old radiatior needed to attach the fans and that's what I came up with. I think the 32 is a perfect spacing for the coils but you could probably achieve similar results using a bunch of different screws. Just make sure the threads are smooth because while unscrewing, if it gets caught, you'll jack up your coil.
I pinch the coil together, no heat, after I install it on my atty (not before because the screw does a great job of keeping the coil perfect while locking down the legs) and it springs back a little tighter, but still with prefect spacing....most of the time, sometimes some tuning is needed.
I think it helps with wicking when the coil does not extend over the build deck, but that is just my theory, YMMV.