Keith,

With respect to the engineer, the proposed revision indicates conflicting datums to me. There is no allowable tolerance and if the axis -C- is aligned in the same plane as the AB line they will be fighting for alignment. Assuming you are still constructing a line between AB, I see no other way of making two holes on the same part a perfect condition. This is why I would suggest using the AB line as my primary datum -A-. Pick up the smaller hole secondary as datum -B- and then align the axis -C- tertiary. Attached are changes to the drawing for your review. I'm no professed engineer but do think this would prove to be more controlled. Your thoughts please.

Regards,

Geoff
Sr. CMM Programmer
Lapeer Metal Stamping
LMS Metrology Lab
Lapeer, MI

Drawing2.jpg
Part Drawing (40,431 bytes)