Cooling trouble on a 440

I have a '67 440 with 915 heads in my '71 Charger. I have a high flow aluminum water pump and a MP aluminum water pump housing (160 deg t-stat with stock pullies). I run fine at medium cruising speed and fast idle (roughly 170-180). But if I am running down the highway at 3500 RPM or the 1/8th mile at 6000 RPM, my temp runs 190-210+. I saw a guy at the track with 906 heads that had nipples tapped into the back side of the heads (firewall side) into the water lines. From there, he runs heater hose lines up to the top of the radiator and dumps right into two newly brazed inlets. Anyone got any experience with this or installation tips? He said he read and article about it somewhere and it said big temp drops and 40+ HP due to cooling the heads. thanks....

I understand what he is doing,but I'm not so sure about the +40hp gain.Don't get me wrong,I'm not disputing what he says,it takes heat to make power and I feel that may be cooling off the heads too much,but maybe he's on to something.I had a similar problem with my '70 Road Runner and it turned out that my new timing set was machined wrong and had the timing at 48 total!!!I had it set at 38 total.I also had my 22" radiator made into a three core unit and now it stays at 160,even on 100deg days.