The original housing and pump are both 440 source- and they are from around 2007-2009 which according to the new research i have done, is the time they had bad flowing units out there. The pump I swapped in was an earlier unit from maybe 06' which cooled a 540 fine.

I have the housing on my race motor that I will pull off and check out, and i will pull the 440 source unit off the 383 and inspect and replace since I have another unit that did cool a BBM.

as far as verifying the temps, There have been numerous gauges from cheap temp mechanical units to what i have in now, all have had different senders.
I can feel the heat coming from it, it is HOT!!!!

The housing is one thing I have not changed yet.

The 383 was originally my motor in my barracuda. It worked in my. I pulled a bunch of stuff off it when I went to a 540, including the water pump and housing. They got transferred to the 540. I gave my dad the 383 years later when he bought this coronet. He bought some parts for it to complete it...

Man.... I hope this is it.