technically yes i guess, but there's not much room to get them on in situ..
I wired mine up with weight on them, using stout wire to hold them compressed, made it a bit easier. You have to then compress the new ones and wire them up to replace them.
If u r prepared to drop the driveshafts off and drop down the end of the beam, then it's not really neccesary - I did as i was trying to short-circuit the process by not disconnecting the shafts.. but i think it was probably just as much hassle either way.