I know this is a pretty basic question, but I'm not educated on the basic up keep, what I mean is I know nothing about boats. Here's the question, I just bought this boat (1986 Bayliner Capri w/ 85 hp force outboard)<br />and I want to check/top off the oil in the lower unit. There is a allen head screw on the bottom, a regular head screw approx 3" up on the right side and above that there are two larger regular head screws side by side about 2" or so apart. I just want to be sure what to touch or not touch. Any help would be great. Thank you in advance.