Amateur mechanic 30 years.
First car was three-wheeled Robin Reliant. First maintenance job was check and re-set plugs. Unskilled replacement of rear-most plug at wrong angle stripped threads on aluminium cylinder head. Second maintenance job - drop engine to remove head for re-tapping - and while at it, re-build whole engine including new shell bearings and crank regrind. A steep learning curve!
15 years later, fitted simple vapour intake LPG kit to 1983 Volkswagen Transporter 1.9.
10 years ago assembled and fitted a DIY Waste Vegetable Oil twin tank system to a 2.5L Peugeot engine wheel-chair minibus camper-van conversion.
Currently maintaining Ford Focus Mk1 2003 through annual MOT inspections.