I tried to find both. An old German company used to carry it in the brand name Hazet.
32mm thin wall. You can buy the one from Princess and just grind it down. Lots of guys do this. It's not so easy using it for the fan clutch as stated. You got to find the right place to slide it through to hook onto the nut. it's rather a tight fit for the M20 engine. works easily for the M42.