Is it possible to bore a 2.6L block to 3.0L specs without any trouble e.g. decreased wall thickness causing overheating or shortened engine life?

I thought both m103 blocks are identical, except 2.6L having thicker walls, however I saw that water passages are different and these two blocks don't look the same.

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2001 E200 Kompressor Avantgarde
1987 300E 5-speed
1976 450SLC
1975 280S (sold)
1973 230.6 (sold)