Replacement of my 68 Corvette's heater core was time-consuming, not because of the factory parts that needed to be removed (There were no options like air conditioning), but because all my aftermarket stereo equipment that needed to be hidden behind the dash had to be removed. All amplifiers, crossovers, noise suppression filters were there and every wire had to be labeled.
I think my car was 25 years old at the time, so I wasn't too surprised that it's heater core had failed.
Bradley, it has not gotten better. I recently had the A/C serviced on a 2002 Chrysler. The car has over 150K miles on it. It runs great, though, and it still gets good gas mileage. It is a really nice car. Now, before having the under dash unit replaced, I had the system checked and recharged. That was not cheap. In both cases the mechanic (on an independent, one a dealer) thought it might be the evaporator under the dash, but becuase of the complexity of getting to it, they suggested trying something less involved, just in case that would fix it. It did not. The evaparator was not cheap, but the labor was 50% more. And, yes, they had to remove the dash. Why these things are designed this way I don't know. I really thought this would be avoided at all costs.
Of course, this has a long tradition. When I was a teenager our neighbor had a 1960 Bently S2. It was the first model with a V8. Now, what they did, was just to put the V8 in the existing body style. The previous engine was a straight 6. Well, to get to the spark plugs you removed the front wheels and undid a panel in the inner fender. How's that for design. You would think that for a car as expensive as a Bentley they would take some time to change the design.
We always had a running joke that on British cars, at least, all the ancillary parts were designed by inexperienced engineers.
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