you can use the same technique using Hamachi over the 'net from different locations. I've not tried it yet but I'm told it works just fine 
Your best bet is to check Hamachi our and see what it does 
Doing this is against the "Terms of service" agreement for the game.
I real strong system isn't essential in building a simpit. Of course the more realistic you make it with working buttons and thing might give you trouble. A friend of mine did
This One. He used a second keyboard and wired his button/switches to the key inputs to get everything to work. When he pulled his flaps lever, it just made the keystrokes.
Mine, which is
<HERE>. Mine was made more along the lines of "a cockpit that houses my game controllers".