I have a force 150 believe it to be a 1990 (model 1508f9a) (serial 16285) this past weekend on the maiden trip the lower shaft through the water pump snapped . The previous owner had work done and I believe a gasket wasn't installed properly and the lower unit was full of water when taken apart. I have found a lower unit from a 1991 it looks like a ( B ) and mine has a 4 above oil plug so I believe it to be a ( D ) . Will this swap work as a bolt on or is there some exchanging of parts needed? First time here and I have learned a lot from reading the posts ,it truly is a great site. Thanks for any help ..Ron
