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Serials 0G202750 and "below" (which is yours) are chrome and can NOT be rebored or honed. 0G202750 and "above" are the Mercosil bores that can be rebored to a max of 30 thou over.
You are better off with the block you have the chrome is pretty tough. Pull the pistons and see what you have a lot of times they are OK with a little cleaning.
M=Mercury. On the #1 cylinder, that is the top one, over on the throttle assembly side it will say either Mercosil or nothing. It is physically cast into the block if it is there.