"Only thing I would do different is use a 180-190 thermostat. ".....
Initial thought was to install 160 stat, to see about coolant flow thru radiator.
Plan to swap (IIRC) a 185F stat long term.
Yes, a slight pita to go back in, but no big deal.

"Make sure using correct fan and if you have a fan clutch"....
I have a 5 blade fan. Blades are not evenly space as a sbc would be.
No clutch on fan.
Shroud is installed. Fan sits ~ 2" inside shroud.

"There were some rubber mastic pieces"....
I will need to investigate.

I have a 350

"There are other things that causes over heating such as Timing and engine specifications.."....
Once I have verified coolant flow, this is next on the list.
I can smell gas out the exhaust, seems rich, stumble here and there on occasion.

"If the plates are all corroded or other issues, ".....
Plates look fine, still stainless looking. The plate that goes in first, does not sit flat in the cavity.
When placed on a piece of glass (only true flat surface I have), you can tell its not totally flat near
the lower radiator hose area of the pump.


"So what temperatures are you observing to make you say the engine is "overheating"?".....
It's peaked at 250-260F, which I know is not good(duh-grin).
If you care, click... https://firstgenfirebird.org/forums...;Main=36899&Number=307203#Post307203
or click... https://firstgenfirebird.org/forums...;Main=36906&Number=307250#Post307250
Since those posts, I did remove the electric fan which did not seem to help much.
Due to other projects, never dug into it much, drove it locally and watched the gauge religiously.

Thanks much.....don t. .....