F355 Challenge Engine rebuild

Unfortunately my recently acquired 355 Challenge shows some unwanted "wear" inside the crankcase. There are four oil nozzles inside the crankcase with two brass arms each. On each sprayer one brass arm has let go (probably a fault of the previous engine builder) and damaged the oil pump gears attached to the crankshaft. There are also pitting signs on the bottom of the pistons and on the rods. Nozzles decided to celebrate a nice party inside the. So probably a huge engine rebuild in front of me.

Been browsing spare parts over the weekend now and stumbled across two pistons & cylinder liners, those marked "red label" and "green label". Can anyone explain the difference between these two? I do have a very good engine builder for the job, just want to gather as much information as possible before pulling the trigger.

Thanks for your help.