I read and watched more than a few tutorials on installing new bearings into the crankcase. None of them have followed what the Yamaha Combined 71-73 service manual for 100-175cc enduros which says: "When installing bearings, pack them with grease".

What do people recommend these days? I thought the bearings for the transmission wouldn't need grease being bathed in the tranny oil.and I thought that the crank bearings get lubricated from the 2-stroke oil.  

They were probably smoking something the day they wrote that.
Just oil them up, they'll be fine.

Pack the wheel bearings maybe if you aren't using sealed ones. But the trans and crank bearings, yeah, what RT325 said.

Cool, muchas gracias!