GS1000L Rear Caliper reinstall not happening?
 

I recently painted the 2 front & single rear calipers on my 1979 Suzuki GS1000L cafe racer project. The breakdowns and rebuilds went smooth for all 3. Both front calipers were a very simple and smooth install, but the rear caliper is giving me some real trouble. The pistons on both sides are nicely settled or compressed respectively, but the space between the pads is very tight ..sqeezing back onto the disc very tightly and grinds across as I slide it in place for mounting. Any tips as to what I'm missing here or would this remedy itself once I get everything going. Some touchups will be necessary after the amount of times I've taken this one apart trying to figure out some kinda remedy. It just seems like a very tight grip in comparison with how easily the front had gone. I should mention this is my first attempt at a job like this. Thanks so much for any help.
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