Hey gang, trying to remove my lower unit on my 2003 Merc 50 hp 2 stroke so I can change out the impeller as it's not throwing water any more while running. I've got the 5 bolts out and the unit has dropped about 1/2" but won't seem to come any further. I've got it in drive and but just wondered if the drive shaft is bound or what I'm missing here, first time that it's been off. Thanks for any suggestions you might send my way.