Yes, thanks, I have used them (Autosparks) for many needs, engine harness for XJ6C S2, and various alternator harnesses on my E-types (I think those wires should be in top condition always), but the problem nowadays is that for instance on E-types etc as the original instrument lighting bulb holders are not available and the new ones. are plastic, you would need an earth wire for each bulb etc.
I nearly fainted too, but the quality and instructions are top notch, every cord looks correct and has correct connectors, even the in-line fuse holders are there where applicable. It was actually the Swiss restorer Georg Dönni who recommended Rhode Island Wiring and I have to say their service was really good and from what I have seen so far the complete wiring harnesses (including also all the instrument panel wiring, as mine was completely replaced by some nifty do-it-yourself mechanic), are really 100% like they would be from the factory in 1950.
Now if I can still find the time and money to actually do the complete body, interior and hood (convertible top) restoration. I am still missing the correct kind of hooding material, but Dönni had some ideas about how you can get it with a special order from Haartz, not easy nor cheap. Mine was and should one day be again: Birch Grey with a Pale Blue interior (I have 12 meters of Rexine in “Pale Blue” and a French Grey hood. (very light grey).