You probably need to do the one at 3:49. And you have to manually rotate the wheel 360 degrees to see where it binds and make the mesh just tight enough. You will have to find the happy medium where the mesh is as tight as it can be without binding at the two (usually) high points (or one) and is not too lose at the low points. It’s a balancing act.
The second adjustment is also sometimes necessary if there is end play in the worm. This allows the work to move back and forth along its axis instead of forcing the wheel to turn. You can observe this when you turn the wheel pulley by hand to where it is moving the wheel in on direction and then reverse the direction while observing the worm movement. It should not translate along its axis. If it does then do the dime adjustment.
Wes, Southport NC
EXos2-GT PMC-8, iExos 100
ES ED 127, 10" LX200GPS+wedge, Astro-Tech 8" Newt, ETX-90, 60mm no-name guide scope ~ 260mm FL
Polemaster, Orion ST-80 and SAG, ZWO 290MM, D5300 astro modified
Nina, Bootcamped Mac Mini control computer, RDP to iMAC
110 amp hour lead acid deep discharge battery for field power
Electrical Engineer, Retired