This is a simple job done easy if you do It right .firstly leave the cups in the freezer over night ,put your frame in the sun, then get a big rubber mallet and belt them in, this takes a bit of strength so don't be a pussy and give it a hit
like they say you need the right tools for the job , so don't use a metal hammer or try put them in with out freezing them ,next Get a threaded rod with some nuts and appropriate sized washers, put your bearing races in the freezer over night put them in the cups instert your threaded rod theough the neck put your washers and nuts on either end and tighten slowly Bam done . ready to install your bearings and dust covers. And incase you don't understand here you go ...