Excuse me, I used some periods which should have been commata - corrected.
The saturated Legend average is the sum of 500 (18 hole) scores, divided by 500.
Take the average, multiply by 500, you will get the sum of scores. 62.36 (average) x 500 (rounds) = 31,180 total shots.
Your average moved by .02 as a result of a change in that number. 62.38 (old average) x 500 = 31,190. Let's ignore the variance (7 - 13) caused by rounding the average from three digits to two.
31,190 - 31,180 = 10 => There's an obvious 10 stroke difference in the total number. Thus the new 56 score should have replaced a 66 score from the past, or a 33 in nine holes.
Your goal is an average of 60.000 => 60 x 500 = 30,000 shots. By replacement of higher scores as explained above, you'll have to strip off 31,180 - 30,000 = 1,180 shots.