Fair point. My reasoning was that, for instance, the technology to manufacture an microprocessor in the Victorian age wasn't there. All the metals and elements existed on the periodic table, but simply even the highest technology in the Empire wouldnt have been able to do it. Fast forward 100 years and we're at a point where you can solder your own printed circuit board in your bedroom - Raspberry Pie computers are another good example. Among a few daft hobbies I restore old GPO phones, but upon the eventual removal of analogue phone lines (as with TV and eventually radio

) there's already little black box on the market for converting the pulse dial to tone, meaning they'll work forever

If there's a demand for it, people will make it. And as technology moves forward the impossible to source specialist OEM-only wire of yesterday will become the easily build up wire in kit form of tomorrow.
Just on the crank sensor side of things... correct me if I'm wrong, but generally it's not the sensor that fails, but the wire that breaks down through constant exposure to excessive heat? - Routing it against the inner wing eliminates this problem, ergo: do this and they should last 'forever' (well, a damn sight longer, anyway). But upon a failed crank sensor, surely it's not an impossibility to replace the wire itself, using the original GM plug and sensor at each end?
As classic parts become hard and eventually impossible to source any classic car owner ends up making clever and lateral choices/modifications. It's been happening for donkeys years and shall no doubt continue. Hopefully!
