I think that you might be trying to place it in the wrong spot slightly, cuz this was the factory's Service Bulletin fix for the FP relocation to resolve the vapor lock problem on all 70-74 914s, & I don't think that they changed the steering rack cover/pan nor the body pan in the 70-74 MYs AFAIK.
It's placement should be over near center toward the passenger side of the 3-4" outlet hole where the fuel lines come out. It should make no difference to switch to a later 2-port pump space-wise, but it will complicate your replumbing to a 2-line system.
Also, the thing about putting the FP up inside under the tank as in the pic above, that I'm sure the factory also considered, is that you then would have to pull out the tank & all the plumbing & other stuff in the way, just to replace the pump or any lines which may leak. Putting it there can easily 2-3x the labor time or cost to do that otherwise simple operation.
Unfortunately I don't have a copy of that factory Service Bulletin to show you, but here are some pix of mine done in the late 70's by my factory trained 914 mechanic (not pretty at this point). I'm not sure if he had to tweak my 73 2L's steering rack cover/pan, but I think not since it looks the same as the NOS one I have to replace the original in my resto. Hopefully it will give you a better idea how to place yours.
Click to view attachment Click to view attachment Click to view attachment Click to view attachment Click to view attachment These weren't taken to show the install per se, but to document my tinworm assessment issues, but hopefully they'll help you placing it. The 2nd pic shows the "box" OE fuel filter up inside the portal FYI.
Good Luck!
Tom
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