This is confusing. I bought the 91385LS from Summit in Jan 2023. It's still listed on Summit for a '65 Barracuda 273,
https://www.summitracing.com/parts/pnx-91385ls/make/plymouth/model/barracuda/year/1965
it fit my stock IBS 4013 just fine. Not sure why Pertronix isn't listing it. Maybe they've dropped that model from the line, I hope mine works well, I'll soon see.
As far as the dist. cap color, I know of no other mag article from the period to show the engine from the angle that you can see the cap. I do have the this from the Jan '65 Motor Trend, it shows the Clean Air Package package, but not the distributor. I don't see any reason the CAP would use a different color distributor cap, a different assembly plant maybe. I found my tan cap on eBay for a reasonable price, I think around $45.
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