These are the casting numbers to look for:
Nikasil M60B30 1 725 970 or 1 741 212
Nikasil M60B40 1 725 963 or 1 742 998
Alusil M60B30 1 745 871
Alusil M60B40 1 745 872
Alusil M62B44 1 745 873
Could it be an 3 at the end instead of 8 ? Wrong reading?
http://www.koalamotorsport.com/article-m60v8.asp