Just did mine the other day, i put the belt on first and then went to put the fan on, realized it was going to be a lot easier to slack the belt again and turn the pulley onto the fan instead of trying to wrangle the fan. Then put the belt back on the give the fan a little snug turn. This is probably the right way to do it but i had to figure it out, for anyone in the future that may run into thisYes. That hardest part is getting the fan off and then back on the new water pump.
Then put the belt back on the give the fan a little snug turn.