Drilling in thick steel- Table saw side

[Jack01]

I think the two sharpie boxes in the pic  are where the attachment mounts. 

I know I would be drilling the cast over the slider although I would align one of the existing holes and drill just one new hole. 

Joe

Joe

Yes I will be drilling in the Table Saw at the marked location
I need to drill 2 holes. The slider do not match the 2 holes on saw. 
It only match one hole which is in center.   
This is Jassem master slide

[Jack01]

Thanks for all feedback

I needed to tap and drill 5/16 -18 hole , in this process i was looking for the right drill which is 17/64

In my google search i came across this site, very interesting. Lot of info on fasteners .I would like to share.

Fastener info

[Cecil]

99--you're welcome.

The center drill is short and stubby, so it won't/can't flex (or worse--break off in the hole) and mis-locate the pilot hole.

+1 on the center drill.  Makes life much more precise.