The -300 is a Classic.
On the -400, bodygear on/off is automatic, so there's no switch to turn it on or off as such.
The tiller on all types only controls the nosewheel, but when the nosewheel goes past a certain point, the bodygear hydraulics are pressurised, (That's when the panel light comes on) then another few degrees of nosewheel angle actually turns the bdygear in the opposite direction to the nosewheel, all done automatically.