Using ER20 collets and commercial collet holder. 6204 and 30204-A bearings. Back seal of the 6204 removed and a grease nipple provided to inject grease between the bearings.
The broach protrusion is adjustable to accommodate different broaches lengths.
The body is the only more demanding part It is turned with the bore concentric and undersized. The bore is then bored to size at the correct angle (1.8 degree)