Things have probably changed since I was in the business, but back then the distributor caps had a little door like this:
FITS ALL V8'S EXCEPT THOSE 1110891 DISTRIBUTORS. 1957-74 BLACK V8 CHEVY DISTRIBUTOR CAP 283", 327", 350", 366", 396", 427" & 454" ENGINES - NEW - MADE IN THE USA -.
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You used a dwell meter and a flexible shaft hex driver like this to adjust the points
Welcome to my e b a y auction/store! Thanks for coming!Up for your purchasing pleasure, a used STANDARD brand number DT-4 DT4 FLEX FLEXIBLE SHAFT DISTRIBUTOR POINTS ADJUSTING TOOL . Standard 1/8 hex
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I'm only 5; 8" and had no problems reaching the distributor, adjusting the dwell, or even timing it if necessary. In the 60's and 70's cars had to be tuned once a year or every 12,000 miles. I would do them on a daily basis, and several a day in the late fall months. Back then a tune up was considered gravy job. You didn't have to wrestle a 300 lb. transmission out to rebuild it, or find a torque multiplier or 4 foot extension to torque the crush sleeve when reassembling a differential.
Having the right tools makes the job a whole lot easier and faster. If you really want a challenge try setting the dwell and timing on a Ford flat head V8. On the earlier versions the distributor was attached to the camshaft at the front of the engine, about an inch or two behind the fan. I can't count the number of old time mechanics that were missing a thumb or finger because they tried to set the timing with the engine running