What should I tell my machinist regarding drilling the main caps deeper and also the oil slinger.

Studs-bolts / What grades?

Standard 312 crank and a block that will be bored

I am going to have him drill the front area of the block for oiling as Tim does and is in Y Blocks Forever.

Any other items to address.Its a mildly smoked over 312.

Oldmics

I ordered an ARP main stud kit from Mummert.

My machinist new exactly what to do.

As far as the slinger area, I did not do that, but you can do a search on here and find out the specs for it or maybe others will chime in.

       A  L  A  N   F  R  A  K  E  S   ~  Tulsa, OK    

If possible, retain the oil slinger.  Although I now have to remove them on 312 cranks that go into the 292 blocks, I haven’t had any oil leakage problems as a result.  But the slinger does still provide an obstruction for the oil having a straight path to the seal so leave it in place if possible.  Many shops no longer have the narrow stone that's necessary to dress the seal area so the slinger ends up being removed to get the wider stone in there.

Lorena, Texas (South of Waco)