You can install a transmission cooler of any type / size / style that he may wish to choose with a 3/8 inlet & outlet. This cooler is to be plumbed in the (rubber) low pressure return line coming out of the steering gear.
Steering gear low pressure return to trans cooler, trans cooler back “home” to the PS reservoir.
Note: If you are (very likely) using the T fitting arrangement to handle the low pressure return from the brake assist unit (as opposed to having grafted in a second dedicated low pressure return line nipple into the PS pump housing), the cooler must be plumbed between the steering gear and the T fitting. Spoken the other way around for the sake of clarity, do not plumb the trans cooler between the installed location of the T fitting and the PS pump reservoir.
Hope this helps!
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