Get a Marti Report if for some reason the original door sticker is missing (often the case). Any car that was originally sold in California will be a plus with regards to value. I doubt it was retro fitted and was a factory install. Dearborn obviously had the parts available. I had a 70 with a 351 Windsor true story there were a few extremely early cars that received the last of the Windsors. It was a special order Dearborn plant built shipped to Los Angeles district 71 and sold new at Russ Davis Ford in Covina CA. The car had the emmissions system in place and was a true survivor one owner special paint (Chestnut Metallic) loaded Mach 1.
I would have interest in the parts.
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