your gonna want manifold heat even in socal. i run hot water on my super six with headers here in vegas, i woulndt do without it on the street. it helps fuel atomization at low speeds, and thus it helps feul economy. here is what i did with 1/2 plate:
top pic: plates with fittings, get water from the heater circut
second pic: notice i opened it up a little bit where the water is coming in on the bottom
third pic: pieces bolted in place, water goes in the bottom and out the top
last pic: still figuring tranny lnkage, this is close to what i ended up with
