Your correct that length, even a little can matter. But you also have to consider the measurements were taken using a tape measure. Not a very accurate way to measure them. I can understand the OP did it that way because he probably doesn't have a caliper long enough to measure them with. Since he said it has ran good with this configuration for 2 yrs. it seems to me it's not a big issue. It's quite possible the proper length would be somewhere in between the 2 and there's enough tolerance there to allow them both to work