Can't comment about Washington's reasoning..about the original question... sure you can having the skills and tools. Drilling holes on housing for sockets for regular bulbs or led strip down the lense ? is about prefference. Wiring? just need to splice the power from parking light sockets in front and tail lights on rear. No need for any extra harness, can be simply home made . No need for 68 or 70 harness donor to make that just 4 wire splice job or 8 if not chassis grounding the sidemarker light.
This has been done and asked several times in the past. Is pretty much a straight up job.
Getting a 70 sidemarker setup could be an option? maybe but would require body job I guess. I think they are a bit larger
Why these ? I can get the rest, but not the specific reason for these aside just easier acces from the driver position... but safety? I don't get a safer disposition but just comfort.
The ignition switch moved to the column was due to the high car theft rate, previously the ignition switch and wiring were mounted on the lower side of the dash and was easily jumped/bypassed being in the column protected it....
Just my $0.02...