This guy tried the welding (unsuccessfully) but interestingly, redrilled the dowel holes and then added more dowel holes and fixed it.

http://www.peachparts.com/shopforum/showthread.php?t=51940&highlight=dowel+pins

i wonder how all that drilling was done?? Put the balancer on the crank and start drilling holes

Here's the answer: Drilled with the radiator in place with a 90 degree drill.

http://www.peachparts.com/shopforum/showthread.php?t=44713&highlight=dowel+pins&page=2

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13