Question of day: 175 pound motocrosser with YamaLink on 2004 YZ250F

Rider is 175 pounds WITHOUT gear. He races motocross on a 2004 YZ250F. Currently using stock spring and it is obviously bottoming with a YamaLink due to the extra leverage and NOT being resprung. The caller/rider wanted to know what spring rate to use. Stock spring rate is 4.7kg. At 175 pound before a YamaLink it is recommended to use a 5.3kg for MX racing at his weight. With a YamaLink at 175 pounds - and using the YZ250 four stroke in aggressive racing - it is recommended to use a 5.8 kg spring and then RESET sag to about 100mm and fine tune based on personal preference.