did this a few months ago.

used the tekno kit from tower for $100 or so.

used 1/8 scale speed passions esc and motor for $170.

had to take apart the tranny to install the single speed conversion.

now if i tighten up the spur gear, i can do wheelies or flip it on demand...

and this is a 2.5 revo i bought almost a decade ago.