This is indeed a long and twisty rabbit hole if you choose to go down it. My attitude is , remove wheel, clean splines and wheel hub with solvent, do not overly apply the grease of your choice ( I will use anti-sieze if I can't lay my hands on some grease but grease that is not too thin is probably best), replace wheel, snug nut before lowering off jack and then tighten with at least a 2 lb mallet of your choice. I do use a laminated plywood tool that is about the diameter of the tire and strike it on the end until I feel like it's enough. Obviously you need to hit it harder the shorter arm you are striking until you get down to hitting the wheel nut ear itself, which for some reason I never want to do. I do think that the longer arm you use, the more you would be able to repeat the tightness you like.
The cars never came with anysort of tool/ extender so I assume striking directly on the ear with a lead or copper mallet by what the courts refer to as " any reasonable man" is sufficient.
Actual torque specs from bouncing around on line seem to range from about 150 foot lbs to 450 foot lbs, or about 200 to 600 NM. None of these numbers were officially applied to our Austin Healeys. I would be loath to use the higher range of this span. Pretty sure 200 ft lbs would be plenty. Your mileage may vary.