3b to ??? engine conversion

[its_that_guy2]

looking at engine swaps at present ... have sourced a 6cyl 4.2d cruiser motor also have sourced another 3b and a 13bt ...

will the 4.2 bolt rite in ? my truck is a 24volt if the 4.2 is 12 what needs to be done other than starter and alt changing .... no clue as to the deal with these pretty much flying blind....

any info would be great also maybe motors etc you know of floating around .. 3b 13bt or whatever but id like to stay with a diesel

cheers shane

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for a 70s swb cruiser