That seems a fair interpretation.
My interest is in establishing factually what shape panel the factory used in 73 on RS and TES since afaik not a different panel. I had an opinion and little doubt but wanted to be sure was supported by credible evidence.
The comments about the BAT example here certainly gave me impetus to look into it today but I’m not that focussed on that listing. After all many RS offered for sale on this thread have had rear slam panel authenticity challenged.
I recognise these photos ( below) are not about the 73 RS; they’re much later cars and US examples but posting them here just to give some comparison. Acknowledgement to Joe Rusz and all other photographers for the images used as evidence
The first is the 1978 911 SC road tested by car and driver in 1978. Note even by then it still has the smooth continuous curve slam panel.
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The article was published in March 1978
Next is the 78 turbo from a US magazine road test also 78 — unlike the SC it has the more angular kinked rear panel
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This article appeared in June 78.
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The datapoints are hardly exhaustive evidence and the provenance of the examples is not as clear as the Jenks road test of the RS but seems likely nearly new cars would be supplied to magazine testers like “car and driver” “road and track”So the difference in the panel visible in two articles oubkished about three months apart goves a hypothesis that the slam change happened sometime doing model 78 or perhaps the 930 first?
Finally the 1980 SC also USA magazine test; a naturally aspirated 911 SC has the more angular shaped rear slam panel so it seems that had now been adopted
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I didn't come across SC engine bay photo from 1979 on quick scan of the www so perhaps the roll-out of the revised panel was completed across all models sooner?
Obviously just three USA datapoints are hardly thorough research but seems in necessary to overrun a “73 Carrera RS for sale” thread with more late 78-80 examples?
In context of model 73 TES and RS authenticity it probably doesn’t matter exactly when the later version of the rear panel was first seen on a 911. Probably “close enough for government work” to confirm (as Hugh had suggested ) it was perhaps 77 or more likely rolled out completely during the model year 78? Roughly five years later than end of the 73 RS production!
Since I have it to hand adding one more image showing the panel on one of the cars used in the RS specific brochure that was put together hastily around end of calendar 72. It is a known early chassis under development so details were not to final spec like the negative script and stickers on the rear panel but still a datapoint as it’s source is clearly the factory known to be taken by a prominent member of the factory when the RS model was brand new:
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I’m not sensing any arguments or seeing evidence to suggesting that the continuously curved shape is the correct on for the 73 RS*.
Steve
*Hugh mentioned an old thread exits investigating the mysterious square on the panel so I suggest pick-up there if there is any energy or new infomation regarding that point.