[Krusekontrol]

You can save money by gutting your exhaust or drill some holes in the back,
The uni is a must
Rejet for the carb 130 is a lot but you can buy a few sizes and move up and down depending on your results based on altitude driving conditions etc...
CVT mods. we just finished the testing on the new shorty clutch and the DR2 variator plus the longshaft pully and the new belt that goes with it. The results are amazing.

You can also swap out the tiny tires for stock buggy tires. You can find the stock tires all over the place. Cheap.

If you want to climb a little better get another sprocket.

There are also new advanced cdi's some are combo (cdi /coil) others stand alone with seperate hot coil. Check with any of the dealers on this site. They are well known in the buggy community and have a long history with buggynuts like myself.

Good luck and enjoy the ride with the kid.