That's a cool lookin' trike Dan!
First thing everyone does is try their "air trike" for size.
You machind your engine mounts? Ooooooh, ain't you posh! Mine are just bits o' tube with nuts welded in the end. Wish I had a lathe -& some idea of how to use it.
Welcome to the wonderful world of triking. I guarantee it'll drive you nuts & you'll wonder why you ever started & how you could've been so enthusiastic & optimistic, but that first blat up the road on something you've created yourself with your own sweat & probably tears, will make it all worthwhile.
Another pair of Triketeers to the cause!