will this carburetor work?

looks like sweet carb, and the fact that it has a primer bulb is cool. I'm guessing the cable hooks up with an L shape if I'm right. You could get a cable like that from Dax, it'd probably fit it. As for that return fuel line I'm guessing it's either a overflow or a pressure one of the 2. My guess is you could just plug that but I'm not for sure though thats something that needs more detail as to what its actually for. Looking at it I'm almost certain it's a pressure line but still not for sure. However if it is then you might need to make your tank air tight but again that's not for sure, though it might work without it. Anyways that's what I say about it, lemme know how it goes.

That kinda carb is designed to have the fuel tank below it (that's why the fuel inlets/outlets are pointing down).
The primer allows the carb and fuel lines to be filled with fuel so that the engine will start easily.
The second fuel line is the return, during engine operation, excess fuel not used by the engine goes back to the fuel tank. If you have the fuel tank up top, the excess fuel might not make it up there.
If you have the tank up top and turn off the engine, any excess fuel in the return line will flow back down into the carb and flood/overflow it.

That carb is like a chain saw carb it will work in any position. for the return I'd just tee it into the feed line. there is a pulse port on that carb to work the diaphragm you will need to make sure it's not blocked or the carb will not work properly if at all. All it needs is that port open to the engine side so a little work with a dremel or small razor slit the gasket to the inside so the port will see the engine's pulses.
You probably will not see any performance gains anyway nothing other than you may think it works better if it does work, which it should.
This carb is more complex and will fowl or get loaded with crap easier due to small traces of trash in the fuel tank so you may be in for some real hair pulling trying to figure out why it's not working good. These carbs have a small fuel filter that is in the fuel tanks for that carb it looks like a small cotton do hicky attached to the end of the fuel line. But if you want to try it go ahead have fun.