The silver end bell 540 was the origional handout 540 motor at titles and the only one allowed at ORRCCA rounds.A few years ago at a vics there was low supply of these motors and the black end bell type were available and we went with these.Since then the silver or black has been ok to use at any ORRCCA round or title.The white end bell is not approved but dont stress if you used one at coleman.No one is being accused of cheating or anything .The ORRCCA guys are running through a few things to be ammended in the manual as this has not been clearly stated.I took the minutes of our meeting at knox and will write them up for everyone to read.