Originally Posted by Steve_sr

Well, I didn't find any spacing differences and didn't even have to tweak the FD. The recent incident occurred because I tried to fix something that wasn't broken!

The 46/30 rings (from a 600 crankset) will mount correctly on the 810 cranks. The only issue I had was that the chain catcher pin had to be shortened. Shimano put 2 scribe (cut) marks on the pin so these same rings must be used elsewhere.