I've ordered my ERA 427 and am in the process of planning my build. Initially I didn't think twice about going with 15" pin drive wheels, but after reading several posts (like this good one:
Which 15-inch radials should I install on my Superformance MkIII?) it is becoming clear that the number of 15" options continues to dwindle. I don't plan to put a lot of miles on the car, but should I worry that in 5 or 10 years there will be few if any options? I'm not hardcore on authenticity, so I could consider the 17" wheels.