Machine the cylinders and get them nikasiled; far better than replacing with OEM parts.
If you do want to replace the cylinder side of the case you will want to replace both the top and bottom as the cases are line bored as a matching set.
Might want to check for roundness as these motors have been known to oval out the cylinders ...under hard use anyways.
You might consider sending the cases to Millennium Technologies to have the liners resealed, especially if you plan to continue racing it and want it to last for a bit. Another option I went with was sending the pistons and bearings to Polymer Dynamics for friction and ceramic coatings, with the added thickness of the coating on the piston skirt also minimizing the amount of rocking occurring within the liner. Millennium was reasonable and PolyDyn was incredibly inexpensive. Only thing I didn't do that I wish maybe I had was to cryo treat the cases and crank prior to assembly, just a few ideas.
Update....i finally got the engine put back together and run across something i could use opinions on..when it came time to install the cams i made sure i was at tdc by doing the screwdriver check and by locking my crank balancer in place with a tapered bolt to help make sure it didnt turn any while putting the cams in. And here is when i noticed something. I was able to get the cam marks lined up with the head as shown in the manual but it also showed in the manual that the mark beside the T on the starter clutch is suppose b lined up with the groove in the cover. For me the T is what lines up. Everything else is set tho. Its at tdc i know by checking with the screwdriver and the cams are lined up...do i need to worry bout this being out of time or since everything else is lined up am i safe?
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