Sounds right to me! Tubular construction radiators were designed to run a high pressure cap, which is what you've got now. It gives you a lot more safety factor in case you hit a slow traffic jam, have air conditioning, or run a trans cooler, which it sounds like you do. An auto trans can put a LOT of heat load into a radiator, ditto with air conditioning because all the heat from the condenser gets dumped right back onto the radiator.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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