I sent an email to EVSEUpgrade and got a very quick answer.
On Dec 1, 2012, at 1:32 PM, Steve wrote:
I have a 2013 Volt which has the new Clipper Creek manufactured 120V charger. These have 14 AWG wiring and are closed with 6 screws. Have you evaluated these new units for possible upgrade?
On Dec 1, 2012, at 3:07 PM, EVSEUpgrade wrote:
We can do that unit with a 240V 13A upgrade for $239. It will no longer operate on 120V however. You can order the rev1 upgrade on our site.