I bent the spindle on my Blade CP and had to replace it. But I did'nt write down the order to relace it. Is it large washer, small washer, bearing, spacer, bearing, small washer, then O-ring?
I was reading another post and their instruction only mentioned one bearing. Are the number of bearings optional?

The first thing you need to determine is if you have the 2 ball bearing or the 3 ball bearing blade grips. If you have 2 ball bearing the spacer is larger and you have 2 bearings in each blade grip for a total of 4 bearings. If you have 3 ball bearing you have a total of 6 ball bearings. I changed the stock order to help keep the collective from sticking, the stock order puts a flat washer with the same diameter as the bearing against it, the outer and inner ring of the bearing both contact this washer which can cause issues. I will list both my order and the stock order leaving the choice to you.

My order from one side

2 ball bearing
screw-large flat washer-small flat washer-spindle-bearing-blade grip-spacer insert-bearing-hat washer with hat facing bearing(flat faces oring)-oring-main hub-oring-hat washer with flat facing oring (hat faces bearing)-bearing-spacer-blade grip-bearing-small flat washer-large flat washer-screw.

3 ball bearing
screw-large flat washer-small flat washer-spindle-bearing-blade grip-spacer insert--bearing-bearing-hat washer with hat facing bearing (flat faces oring)-oring-main hub-oring-hat washer with flat facing oring(hat faces bearing)-bearing-bearing-spacer-blade grip-bearing-small flat washer-large flat washer-screw.

Stock
2 ball bearing
screw-small flat washer-large flat washer-spindle-bearing-blade grip-spacer insert-bearing-hat washer with hat facing bearing (flat faces oring)-oring-main hub-oring-hat washer with flat facing oring (hat faces bearing)-bearing-spacer-blade grip-bearing-large flat washer-small flat washer-screw.

3 ball bearing
screw-small flat washer-large flat washer-spindle-bearing-blade grip-spacer insert-bearing-bearing-hat washer with hat facing bearing (flat faces oring)-oring-main hub-oring-hat washer with flat facing oring (hat faces bearing)-bearing-bearing-spacer-blade grip-bearing-large flat washer-small flat washer-screw.

Also, the number of bearings isn't optional, it is determine by the blade grip. It isn't possible to put 3 ball bearings into the 2 ball bearing blade grip. Also, when you assembly it you may notice that the you can slide it slightly from side to side, this is normal with the stock setup, it allows each blade/spindle assembly to pivot around the main hub. You can add more washers to tighten this up which will make the helicopter more responsive, but less stable.