I am curious about a few details.
I have a BC-NNN binding I'd like to swap out for a Salomon SNS - XA binding. The two appear to have the same toe mounting pattern with the exception of the SNS having one additional screw centered at the front. If that holds true, is it ok to reuse the existing holes drilled for the BC-NNN binding? Also do i apply a soldering iron to the screws to heat them up and soften the glue to extract them?
I'm also thinking the other option would be to just drill a second set of holes a few millimeters away from the existing ones which will probably align the SNS boot with the skis center line rather then it being located behind it due to the SNS boot bar forward location. The BC-NNN boot bar is a little reset under the toes which i think allows for a more natural and easier pivot lifting for the kick and glide.
I haven't had much luck with BC-NNN boots. Tried just about all of them. Either they have horrible forefoot flex break points pinching inward at the Metatarsal Heads or at the cuticle base of my big toenail, or they have a heel cup that is to wide providing no support. The only BC-NNN boot i haven't tried is the Alpina Alaska so the possibility exist of going back to a BC-NNN if the SNS doesn't work out. I'm gonna try not to think about that one now. The Salomon X-adv boot has a tighter fitting heel and seems to be pliable at the forefoot flex break point. I've read of similar boot troubles, some say not to bother with BC-NNN boots, rather use a skate-ski combi boot for the narrower full metal edged BC-XC skis.