Have currently got the head of and fitted 10 new valves came to refit cams and was not sure if I moved them on the strip down. Tried to identify which was which but no A or E marking on either shaft. The only difference seems to be 2 grooves on each shaft which are approx 5mm apart on 1 and 12 mm on the other does anybody know if this denotes Ex and In and if so which?