You should be able to just do a standard short mixer test on them. Looking at the manual it looks fairly standard (page 29):
flysurfer.com/files/dlm_uploads/2017/05/SonicRace_EN_2017-04.pdfI can try and help if those instructions don't make sense but it looks like a standard flysurfer mixer so you should be able to see a lot of videos on utube. Basically you move the knots on the grey line to line them up. You need to adjust A and Z to get a consistent angle before you start. If you get a couple of tent pegs and anchor the metal rings about 8-10 inches apart, you can then move A and Z left and right until they match up (think trigonometry changes). At the point where A and Z match - thats where you should leave the lines and do the mixer test. Its important to have that angle right before you start though as it changes the pull on the pulleys.
Worth checking the lengths of yellow bridles are consistent for each side though (tape measure is enough). They can shrink so you end up with different bridles but a tuned mixer test on each side.
Good luck. Only just figuring this stuff out myself so I know it takes a little time to get your head around it if you've been on LEIs beforehand.
