Replacing whole fuel kit?

Just a couple questions on the "kit" for fuel in the '74 Gold Dusters /6. My Fuel Sending Unit was shot from when I bought it, I believe a wire was snipped and just generaly trashed. Tank was leaking and straps had to get cut to be removed, so with that said, I'm building a shopping list and want to make sure I have everything I will need.

1974 Duster Fuel Kit
1. Fuel tank Mine was one with the filler hole on the left, drivers side.
2. Fuel Tank Straps
3. Fuel Sending Unit*
4. Fuel Pump/Fuel Pump Gasket
5. Fuel Filter Will just buy from local Autozone, NAPA, etc..

Am I missing anything? I plan on going V8 swap later on, so I believe I will need a different FSU/Fuel pump, later on. But for now just to get a good Fuel set up, is this everything I need to replace my existing fuel set up? I still have the gooseneck and cap.

* Need Help Picking These Parts Out

Fuel Sending Unit - Not sure which one will fit, there are a couple options. The tank says the size is 29-3/4 x 19-1/4 x 10-3/8. Does that mean the FSU has to be made for a 3/8 hole? Also, the "Lock ring kit" that is included in the tank purchase, is that the same as the "FSU Lock ring"? Some FSUs have Fuel Return, is this needed, or is it just an option?

As always, you guys are super helpful. Thanks for the help!