Original owner Honda BF 130, 1999, salt water use, lobster boat, 2000+ hours, removed lower unit numerous times to replace water pump, This week remove 5 nuts on studs, lowered the lower unit down 5 and half inches and the drive shaft has hung up. it is splined into fly wheel boss and should freely drop. I have Honda serivce manual and no help there, has anyone experienced this and how to get lower unit to drop free?