What are you trying to accomplish?

I suspect that kit will work. The main trick is to get the rear cog to line up perfectly with your front chainring. You'll have to experiment with the cassette spacers to make that work. You'll need the chain tensioner because the vertical dropouts won't allow you to adjust the chain tension otherwise. The chain that you have will work fine unless you switch to a thicker chainring and rear cogs. You will, of course, have to shorten it.

Functionally, I don't see what you will have gained over just not shifting and, to me at least, the chain tensioner ruins the conversion stylistically.