Ok here we go. ITR pistons will fit in the LS, and will fit your stock LS rods. Your head doesn't need to be modified. New rings are about $90 I think, but I'm not positive. Until you actually take your LS pistons out, you won't know if you have to bore the cylinder walls. If they are scored, you will most likely have to have a machine shop bore the cyilnders .25mm over, and get .25mm oversize ITR pistons.
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