Keep the OE 74 exterior look & update the interior.
Orrrr............. Since swapping doors = painting the inside & out, you could always do a 'reverse skin' on the doors & use the good side (interior side) of the OE 74 doors & splice them to the newer doors & utilize the 74 interior panels. Just depends on how anal you wish to be.
Will you need/want a notched x-member for this one? Prob have 1/2 ton spindles & stuff if you need 'em as well as big brakes too....