if the crank won't turn now ,then the bearing are pinching on the crank
what-ever you do - do not use a breaker bar to turn it over.
bearing should not be hard to install
take the caps back off -all of them -these need to be installed back in the same location and position they came from -don't mix them
remove crank -insert the bottom-half bearing in all the journals ,make sure they are setted -lube the bottom half bearing /use the right half of the bearing
now set the crank in it's journal's - rotate the crank (-remember the lube on the bearing before putting the crank in )
rotate the crank ,should turn very easy ,now install one of the top caps -add lube to the top half with bearing half installed ,
torque it down evenly at half it's torque spec....rotate the crank...it should still turn over very easy..do this with all of them ,once they are all installed go back over all of the cap bolts and one at a time torque and rotate crank each time ,torque them to the proper value
there is nothing hard about installing bearing
if you have never done this before ,it's best to ask someone who has and how they did it and maybe what to look out for while doing such.
a shop manual isn't bad to have at hand either - know your using the right torque spec for what you are doing
ask if you don't know -get it done right the first time
good luck
cheers
steve