It’s often cheaper and better to just have FS or ATL make you a bladder, then just make you own cell can. Can use their filler necks or make you own. Tis what I did for the subaru.
Remember when making radiator ducting…initial opening at front of ducting should be smaller and have the duct work taper up to the core of the rad. Cuases high pressure at the front opening and low pressure on the backside, airflow slows down over the core and absorbs more heat. People just assume that a shit ton of airflow across the core is always the best move and it’s not always the case. If the heat can’t transfer to the air it’s not going to do much. IIRC, quick reference to the formulas are in C.bells Max Boost book.