The Sept. 23, 1969, primary election for delegates to the sixth Illinois Constitutional Convention was only a prelude to the general election on Nov. 18, 1969. The primary was held to winnow the number of candidates for each district to four. The general election was held to choose two delegates from among those four. The general election produced some surprises.Only 50 of the 58 districts held primaries. In eight of the 58 districts, there were so few candidates that there was no need for a primary.In the 50 districts …