Shaun, If you are talking about the Chip Hyde Double Vision this has been converted before. Although larger than I normally fly the following seems to be an often used set up for 50cc conversions....
12s 5000 and up lipos
100amp HV controller (Various makes)
Hacker A60 18L motor
XAOR 24 x 10 prop.
This should give about 27lbs thrust if your lipos are good ones. Current draw at WOT would be about 75amps.
Dare I say that you will get a lot more info from the giant electric forums on the RC Groups site.
All the best...enjoy your flying/converting...Chris UK.