"Rocking it down" is definitely not a good idea. It must go in as close to perfectly straight as possible or damage can result. On early engines it isn't a real tight fit and can sometimes be (carefully) slipped down into place with nothing more than a deadblow hammer. I do use four long bolts as guides while driving it into place.
Failing that, I use four long, fully-threaded bolts with nuts and washers to "press" the bearing into place. You just need to be very careful to turn the nuts equally so that the bearing will go into the case opening straight.
I use a light coating of Permatex Super 300 on the case and bearing sealing surfaces in addition to the gasket. Be sure to apply sealer (I use a liberal coating of Hondabond 4) to the two lower bolts of the rear main bearing. Those are below oil level and will leak if not sealed. Same with the banjo bolt on the oil return line - even though it has aluminum sealing washers, I apply Hondabond 4 as well.