Get the 22mm carb. Runs much better with that on there instead of the 20mm. Also get the big UBI filter http://dratv.com/po12.html 
You'll need the manifold turnout and might need to "massage" your fuel tank just a bit.  
also... 
Fuel line and filter(s) 
Randog bar riser- every cool atc needs one 
exhuast 
Some sort of custom battery tray 
starter switch and kill switch 
shifter and wider peg set from http://hondaatc70.com The peg set isn't on their site, but contact Gordon. He'll get you set up. http://hondaatc70.com/contactus.aspx 
and a DDR sticker 
There will be several orders placed through DR ATV once you get going and realize you need this little thing and that little thing so be prepared. haha 
Here's my build thread is you need some ideas... 
http://www.dumontdun...showtopic=13353