79 KZ750 Cylinder Block Removal help

Hey everyone, having some issues trying to get the cylinder block off. I have the Cyl head removed and now I can't seem to see what the issue is. I think the chain guide fell down and now it's not moving up back to the front of the block, therefore not letting me remove the block. I can't move the rear guide forward as well since the front guide is in the way.

Also I have attached a pic of the cylinder head and was wondering why one valve is reddish-brown?
Should I bring the block and head to a machine shop?

Any help would be greatly appreciated.

Aren't there two 10mm bolts fore and aft holding the block to the case?
Steve

Steve, yeah you're absolutely correct, and I forgot to say that all the bolts and whatnot are off. I can't remove the rear chain guide because the front guide fell down in between and can't be moved back up and out of the way. I am hoping I don't have to take the bottom end apart now that the front guide is in the way.

As per my pictures above, I managed to somehow get my forward chain guide with its respective sprocket stuck in-between both pistons in the valley. Today, I managed to unstick it by prying through the chain tensioner hole, using a thicker punch and leverage. Once I was able to remove the tensioner and sprocket the cylinder block came off in no time! I don't know if anyone has had this issue before but it was very frustrating for me. Also I'm a nub so there's that but I enjoy the learning curve.