looking at these fuel pumps and trying to figure out what they mean by "(use with inline check valve)" ? scroll down a bit and there's two types of fuel pump for the same model... heres the link
www.crowleymarine.com
1991 Outboard 75 [ELPTO] [1075412LD] - Parts Lookup | Crowley Marine
View parts diagrams and shop online for 1075412LD : 1991 Outboard 75 [ELPTO]. Offering discount prices on OEM parts for over 50 years. FAST $4.95 shipping available.
www.crowleymarine.com