I would not put two dwarf gouramis in a one gallon tank. Sounds like a bad idea to me. They tend to be sensitive to water quality and in a tank that tiny, the water stats tend to jump all around unpredictably. Also, it would be overstocked with four inches of fish in a single gallon of water. And thirdly, gouramis are territorial and the lack of space would almost certainly lead to an eventual fight, where the stronger one tries to get rid of the weaker, and most likely will be successful since he'd have nowhere to hide.
I don't mean to be negative but you'll need to take at least one back if you're looking to do the right thing for the fish. That would leave you with the first problem, cut the second in half, and eliminate the third. Gouramis don't mind being alone since they are territorial.