I have a 1976 evinrude 40hp. When I removed the gearcase, the driveshaft stayed in the powerhead and came out of the gearcase. Don't know if this is a problem. I can't slide the waterpump housing past the impeller key this way. Tried locking vise grip on shaft and hitting down to remove shaft but it will not budge. Any idea on how to get the shaft out of the powerhead? Is there another way around installing water pump housing?