@Rockabilly John, that's exactly the issus. Apparently, no difference.
@Stantheman I asked for them to be wheighed and apparently (just phoned the shop) their wheight vs. Mk III is the same with a meaningless difference that could well be explained by the "mod" we did here to the cracked Mk IIIs.
Also, the mechanic from the workshop told me that the horizontal welding was in fact at the bottom of the silencer in the MK IIs (they still have them there) but now that my son took the M3W to the shop he checked and indeed the welding in the Mk IIIs was also in the inner side of both silencers.
The mechanic's verdict is that these exhausts are Mk III. He doesn't say it that way, of course, but he says these new exhausts are 100% identical to the previous ones.
HE even asked me if I'd prefer to keep the ones he "made" with the remains of the cracked Mk IIIs, or if I wanted to perform the same "surgery" in these. Of course I replied "no". To alter the parts MMC sent me would void their warranty, and to simply not use them would not be smart.
So, there you have it. Onwards and upwards, fearing not the crack(s) of Doom!
