Joe, I was looking up part numbers and see that the 1200 and the 1000 call for the same o-ring size on the oil orifice, the one that goes from the head to the block, but the part numbers are a little different for the actual orifice, the piece the o-rings go on. Have you investigated if there's any difference yet? The Honda numbers are the same in the front, 12238. But the endings are different. The 1000 is 12238 371 000 and the 1200 is 12238 mg9 000. I am guessing they are the same. Maybe Dan can cross reference these for us.