Prior to this rebuild (3+ years ago), I have been working on a A518, and this clouded my memory now about the 'number of springs'.
Went back looking at pictures I took of this A500-rebuild, trying to refresh the memory when it came back to me again... lol
Yeah, 42RH is a single spring like a 904.
The front clutch restrictor doesn't do a lot in my experience. The O/D valve body plates typically have two holes in the front clutch apply port with a check ball in the valve body. I believe that was there to soften the shift into reverse. If you used an aftermarket plate with a single hole and left the check ball in there that could be part of your problem. Chuck that ball in to your junk drawer.
The old vb-plate had extensive damage where the check-balls had been 'hammering' away at the plate. Some almost made it through the plate. This led me to use the TransGo supplied vb-plate in the kit.
Pics below;
