.
I am currently under the assumption that the Edelbrock heads require 10° less ignition advance than the OEM iron heads (until someone reports otherwise). So if the ignition is set up for 36° to 38° total advance, the static advance should be dialed out (retarded) by 10°.
Unless the overflow tank has been converted to a head tank, the top of one of the radiator's tanks needs a drain petcock screwed into it to serve as an air bleed. The factory air bleed doesn't function properly, Ford/De Tomaso tried about 3 different air bleed configurations, none of them ever worked. Wherever the factory air bleed connects to the coolant system needs to be disconnected and plugged. Manually bleed air from time to time or convert the overflow tank into a head tank. Either of those methods work.
Make sure there are no sections of radiator hose between the radiator outlet and the coolant pump inlet that could collapse due to vacuum. Gates green stripe hose, wire wrapped, (vacuum rated for 25” Hg) should be used between the radiator outlet and coolant pump inlet. Part number 24922 (1-3/8 inch - 35mm - ID hose) for most sections, and part number 24928 (1-3/4 inch - 44mm - ID hose) for the connection to the coolant pump. Those parts numbers are for 5 foot length sections of new hose.
Flow Kooler's coolant pump p.n. 1648 is designed to improve coolant flow at low rpm.
IPSCO sells a smaller diameter pulley for the coolant pump. This increases the speed of the coolant pump by about 10%. The "overdrive" pulley's part number is # IPS260-OD. Every Pantera should be equipped with one of these.
Since the radiator fans are DC, if the polarity of the connections is reversed, the fans will blow air in the wrong direction. So make sure the fans are blowing air in the proper direction.
I have seen the metal coolant tubes running below the car full of iron "chips, or rust. That could plug things up.
For your peace of mind, 93 octane fuel should be fine. Based on the mechanic's 10.4:1 static compression calculation, I calculate the intake valve closing at 68° ABDC (278° intake duration, 109° intake C/L), thus the dynamic compression is 8.09:1, which is just a little high for 91 octane.
There are a couple of issues I'd like to go over with the engine rebuild, not related to over-heating. I don't want to distract attention away from the subject of over-heating, so perhaps pose your request for comments about the engine build again at a later date, after the overheating is resolved.
Finally, Eric,I love the picture of you and your father in front of the Pantera. I would like to use it on the home page as the next picture of a member posed with his Pantera. Would that be OK?
-G