The fact that you even considered using a square tank to store liquefied gas under high pressure proves that you will be better off buying an NGV kit than DIYing your own!People out there interested to DIY a NGV gas tank....come and share some opinion....Does a square gas tank possible to use rather than a cylinder??
re-route some injector to NOS tank.I wonder sequential kit can put nos inside or not..since it has its own injectors..haha