I used the following to shim both my FLM Hybrid Bulks
And I got them here.
One pack comes with 3 different thicknesses, and they're stainless steel. Worked like a charm I thought.
The shim you measured that comes with the bulk goes in one side before the bearing goes in, it helps to shift the diff to one side or the other for pinion mesh. But shims are still needed. Do not put the shim that comes with the bulk inside, it has to go in the bearing seat, towards the outside. Kind of hard to explain. I can get you a picture if you need.
-Travis