The Marti report is derived from the "Eminger" report, which is one of the copies of the actual invoice that was sent along with the car when delivered by the Motor Convoy carrier. It contained base/standard equipment and options, with retail and dealer costs. This document was how the dealer was invoiced and allowed them to add the vehicle into the dealer accounting system and inventory. If it wasn't on the invoice, I can assure you; that it didn't leave the assembly plant with it. Since that is an original Ford-produced document, I would put more faith in it than anything else offered by anyone. As nice as the Marti report is, it is not a Ford-generated document but is a compilation of what Marti's staff interprets as being on the vehicle. I have found a few mistakes in the optional equipment listing on some of my reports. I am not knocking the Marti reports, as I have a fortune invested in these reports on several of my past and present vehicles. These are reports that the GM and Mopar fans wished they had for their cars. They do an excellent job filling in the blanks but leave many items between the lines to sort out.
There was a go site for all things Sprint that appears to be no longer functioning. Daniel Russell ran the Sprint Registry and possessed some rare dealer literature that enabled him to answer any Sprint package/option questions you could throw at him. Although most of us have never seen a vinyl roof Sprint Mustang, it is feasible that it was an allowable option. As with the '71 Special Value Mustang (Spring Special), a customer should have been able to order any option as long as it did not cause a de-content or a conflict with the A or B Sprint package.
As Hemikiller posted, the buck tag would be another alternative to check for a vinyl top option. Since it would require the roof panel to be punched with the molding holes to avoid paint damage, this would have been during the "Buck" process. The color on the right side of the tag would let the body shop personnel know it was a vinyl top color. Most '72 models have tags on the left side of the radiator support behind the headlight assembly like the '73s. I have found some on the passenger side as on the '71s. Don't be surprised if you only find a screw and a piece of the tag. They are made of fragile, thin aluminum and are easily damaged.
If you are still unsure or want further verification, I suggest the Eminger report/Ford Invoice. As I previously mentioned, if it's not on the invoice, it did not leave the assembly plant with it!
