Nice, i got barricade too.
It's cool and all, but i got the normal headlight and tail light upgrade, as well as the modified-hood and flashing police light bar too.
To anyone else thinking about doing the same, i have a word of caution for you:
It is not possible to run both light kits at one time.
My limited knowledge of electronics seems to suggest that the resistance of headlight/tail light kit seems to be less than that of the overhead police light bar, and electricity like to flow to the direction of least resistance. I'm sure there's more going on there than that, but you get the idea. at any rate, when both kits are connected, the light bar DOES light up, if you hold it to your face, in the dark, and squint. Otherwise it's not noticeable. The normal lights also suffer in their performance ability as well, becoming dimmer.
I got 40ish minutes out of 4 AAA duracell batteries, i'd recommend decent rechargeables. That, and, it is possible from what i've read online to modify the vehicle to accept a 5th and even 6th AAA battery to prolong usage time, as the internal electronics will allow this much more current. Do not connect a 9v battery however unless you like to see how much smoke can come out of your xmod.

i'm just saying it's possible, and it's not my fault if you ruin yours or it blows up in your face; i'm sure you could find a tutorial somewhere about how to do it properly.
I hope this information helps.
Also; does anyone know how to fix the problem with the light kits not-working at the same time?