On Sunday, May 28, 2017 at 10:32:20 AM UTC-4, wrote:
Distance from datum to main gear may (will) vary due mostly to shock absorber being somewhat compressed. Best to block the gear in the full down position, then measure that distance. Remember to do all measurements with the ship in level position. Weights at known accurate distances will produce accurate results.
Hope this helps,
JJ

JJ - thanks ... kk