Been there did that.
With exhaust, it did improve things for more fun.
Without after market ecu, fumes would burn your eyes at idle.
You will not pass emission.
Believe it or not, get a turbo fly wheel, take about 7lbs off it, get a turbo clutch, and balance the flywheel and pressure plate.
This will not effect emissions but will have a noticeable increase in the butt dyno.
Then get an after market ecu, (megasquirt) and learn to tune!
You can always use these parts later in a different build (earlier) model.