i remember back when i was 18 with my Gregories Guide to every thing I needed to know about my coupe, i thought i would have a go at doing the tappets, this was a safe move as i was having the car servcied the next day, so i read the section on tappets over and over again, went and brought the little spacer thingy, and changed my tappets i wont use the word Set as i didnt do a good job, the little A12 was tapping its head off, next day at the mechanics, the guy tells me he couldnt service it until he had fixed them, i blamed my dad for tinkering with my car, that he thought he knew what he was doing, and my ability with a spanner has never increased, unfortunately