Today I learned something that I bet a lot of you already knew. My 230SL had a 129 block replacement early in its life. I sent the 129 replacement block off to Metric Motors, (those guys are great!), two weeks ago. I had talked to a couple of 113 guys who told me, "All 129 blocks are 250SL blocks". Made sense to me. Anyway, talking to Mike at Metric Motors today he told me I had a 230SL block, even though it has a 129 casting number. Because....... it has the four main crankshaft. Here is the question I am posing to my fellow Pagoda owners: At this stage, with the engine out of a spectacular, perfect body, west coast, super clean 230SL, do I put the 129 block back in, or have Metric Motors swap for a 127 block and have it re-stamped with the original engine number?