Looking for some affirmation (8 3/4 rebuild not successful)

your pattern looks really good ,,what did you set the preload at should be 20-25 in/lbs with new bearings ,,,, but your thinking is off on the pinion bearing preload set up --- you stated using the solid spacer and a thinner shim locks up the assembly ( which is correct ),, with that situation you would then ADD shim ( increase the thickness ) maybe .002 at a time ,, torque the nut to at least 150 ft/lbs and check the preload ,, by cutting down the spacer you are taking shim out and going the wrong way.
one other thing to check is the I.D. of the solid spacer at the big end .. sometimes these spacers do not sit down flush on the bearing and have to be opened up at tad ( honed out ) to completely seat flush onto the large pinion bearing.