fuel injection fuel filter installation- why the difference?

still waiting for the darn dealer to get my fuel filter in but when it does come i want to make sure i install correctly. the old one was pretty much plugged off and installed with the "in" on the bottom. this is where the tank hose was coming from. before i looked at my classic supplement and fuel injection troubleshooting manual, i looked at the 1980 z1000-h1 supplement in the kz1000 service manual. this way seems like the as long as you have fuel coming from the tank then there would be no air trapped in the filter going to the pump. i checked the other manuals and saw a parts microfiche on babbitsonline for the Classic model and although the filter has the "in" on top, the tank is actually feeding the bottom of the filter. i'm going to install it the way my classic manual sez but why does anyone suppose there are two diffrent installations??? maybe the H model has the fuel pump located at a diffrent spot then the G (Classic) model. just guessing here. and to make everything clearer i scanned both installs and will include them here.

I have an 82 GPZ1100 B2 and the same question always came up for me. I have the shop manual and have followed it over the years with no problem.

My fuel pump is next to the battery and I cannot figure why two filter set ups are listed.