I have a question about a Minneapolis Moline 445 that Im helping a gentleman with. The hydraulic pump that is on the back just below the third link is not working. So I took it off and theres no sleeve/couples connecting the shafts together. So, Im guessing someone has taken this off at one time. Or, is there not a sleeve/coupler needed? Also the three point is not working. Is that because of the hydraulic pump not having all the parts? Im new to Minneapolis Molines and Im not having much luck understanding this tractor. Ive worked on John Deere and Internationals. Could someone help me understand? Thank you!