Oil pump on a 304

I think tomorrow I'm going to install the oil pump rebuild kit for my

304. I picked up my Chiltons manual a few minutes ago to see what I was going to be in for and it looks SUPER easy like I just have to remove the piece that the oil pump screws onto and the gears of the oil pump will be right there exposed. I was thinking I was going to have to remove the oil pan and go in from the bottom. Several people made comments like "While you're in there check the crank bearings" so I'm wondering if I'm missing something? I mean I know that worn out crank bearings could cause low oil pressure but it just sounded like I was gonna have to drop the oil pan for this because of the "while you're in there" part of the comments. I guess I'll just do the oil pump rebuild and see what that does for the pressure and if it's still low I'll drop the pan and start looking at the crank bearings. I guess y'all meant "While you're addressing the oil pressure problem" when you said "while you're in there?" Thanks.