My mate is a Bellend!

Hello everybody, as the title says.... My mate bought a new battery for his Daytona 675, and then promptly plumbed it in back to front.... DOH!
I'm going up to help him fix it on the weekend, but have never really been under the skin on a 675. I'm guessing that he has blown out the main fuse.
Where is it located?
Anything else likely to have blown?
Anyone else dumb enough to do this?

Cheers for any answers.
Ive also posted this on the Daytona section too

 

The main fuse was intact. Randomly it blew out a 5A fuse for the tail light, but all other fuses are intact. We put a different battery on it and no dash lights or power.... His head in his hands at this point...
So, now I'm thinking the Reg/Rec or the ECU..
Anyone?

 

We found and checked the main 30A fuse, all OK. Yeah, could be a fried ECU.... He has given up and given it to the dealer, big bill coming his way... I offered my assistance but... he would rather pay over the odds.. so crack on eh..

 

As it turns out.....
The bike has not one but 2 30A fuses.. we found and checked one under the seat, which was fine, however a second one lurked under the tank... which HAD blown out.
Simple and cheap fix. Phew.
He is still a bellend tho!