I´m having a hard time finding bearings (std size) for my mercruiser 496 Mag 2005. It looks that the rod bearings are the same as old style bigblock (454, 502 etc.) but I´m very insecure about the main bearings. Anyone know fore sure??

Yes. the gen 7 8.1, 01 and newer shows a diff part number but I hear the 4.375 crank goes in a gen 5-6 block.

Mercruiserparts.com has a bearing kit for 94.00

496 main Journals same diameter as the 454 and 502 = 2.7482 - 2.7489

taper, out of round and main bearing clearances is different specs thru out between all. Just saying