Rear bearing(L-R [and parallel to blade])
Lower bearing(L-R)
Upper bearing (L-R) (and same at top and bottom of post position) [This positions the post parallel to the blade(L-R again)]
Upper bearing (in-out) (and same at top and bottom of post position) [This positions the post parallel to the blade, but this time in-out] FWIW that is NOT vertical!
The inclusion of the split backup bearings adds to the complexity of these adjustments. The L-R adjustments become more critical.
As you demonstrated, one must 'sneak' up on the final setting, and hold the screw positions when securing the jam nut so as to move the two screws in equal as well as opposite direction.(and readjust tension by moving both screws the same amount in the same direction while doing so)
I feel a need to observe that the blade is not allowed to deviate from a tangential line between both wheels during all of this.
Quite easy to 'get lost' while doing all this!
Be thankful for success the 'first' time!!!!!

I hope this 'summary' highlights the crucial details of your procedure and helps others.

