Great build! I'm quite a bit concerned about your safety however:

I'd prefer it if you could bolt the nitrous bottle and the amp directly to the body, prefereably with stronger bolts and bands on the nitrous bottle (you can add thick steel plates under the body to spread the load around the bolt heads as well). You do not want to have these two things flying around in case of a (Khuda na khawasta) crash, how light it might be.
Play it safe bro'! Cheers!
Sami
p.s. Are you thinking of putting in a roll-cage? It's a good investment as apart from the safety improvements, it stiffens up the car, increasing the life of the body shell and can potentially improve launch consistency, since the suspension will remain straight and true.