FORCE : 50 H.P. (1987) Model Serial Ranges 507F7A 507F7B 507F7C 507X7A 507X7B 507X7C 507Y7A 507Y7B 507Y7C 508M7A 508M7B 508M7C 0C507F7A 0C507F7B 0C507F7C