With todays gas does reading the spark plugs tell us anything, will they still show a lean or rich mixture, I pulled the ones out from the 59 AB I just went thru the carb on and they are almost as clean as they came out of the box, hardly any color on them just a slight brown tinge,they've got about a 100 miles on them, I ran the truck about 30 miles after working over the carb and it seems a little lacking in 4th gear, I'm thinking a little lean but wondering if todays gas just burns too clean.