Anyone know why are there two thickness of crankcase housing bearing sleeve thickness options?  Thick or thin, blue or red, which one do I use when replacing the crankshaft. Do I Use both blue for left side case and red for the right?

Can't remove the middle drive shaft to have access to the bolt circled. Also can't remove the front shaft housing also circled in the photo. Is there a special too needed to remove this shaft?
Trying to split the case apart to get in the transmission, but won't budge. I'm thinking it's because of that one bolt behind the shaft I can't have access to.

I have a 2015 Zforce 800 EX. I'm attempting to adjust the valves, and according to the service manual i need to alighn the two parallel to the base of the cylinder head. This sounds a bit odd to me, why not line up these lines with the top of the head where the valve cover mounts? It's easier to see and line up. Anyway when I line up the cam gear marks and reference them to the mark on the mag flywheel, Its off a little. Either way, If I line up the cam to tdc the flywheel mark is a little off, If I line up the flywheel mark to tdc the cam gear marks are then off. However, the engine runs fine and was just checking the valve clearence. To me this looks like its a tooth off, how can that be if the engine runs fine. Has anyone run into this before?