Thank you all for the help. Problem solved. Solution was to test for sideplay AFTER tightening bolts. On youtube some videos say you should test for sideplay after preload and only move on to bolts if there is no play. This worked on my old FSA cranks but doesn't work on Shimano. I can also see now from videos that its normal to have 2-3mm of crank go past the end of right arm spindel. Cranks look good and run smooth. Lesson learned. For your information I can confirm that shimano cranks are strong enough to be hit with a rubber maul some 50 times no problem.