Block crack 750 R1

So I knew going in that the bike had an oil leak on or around the chain tensioner area. Was hoping that it would be a gasket or loose bolt but it seems to be a crack on the block. Anyway, I bought the bike and it came with a spare motor that the PO bought for parts so that won't be a problem. Good times

My question is what else should I replace while the motor is apart. Valve guides? Cam chain? Any suggestions would be greatly appreciated...

Oil seals. Check the condition of the chain guides. Ball/roller bearings. Clean the cases including the oil galleys. Check the rods on the crank before disassembly for worn bearings.

Since you have a parts engine you can go through both engines and use the best parts from both. Main thing is to inspect everything carefully and be sure nothing is too worn. The factory Kawasaki manual has specs for everything.