drilling cast iron?

[Vee]

I need to extend my front bumpstops. I search and found that some guys have issues with the frame cracking by just adding a spacer to the bottom of the stock mount. I want to add a solid rubber spacer to the top of the leaf spring clamp which on the front axle has a much thicker center section than the rear. do you guys see any problems with screwing a self-taping screw into the top of it?

 

[rdn2blazer]

I need to extend my front bumpstops. I search and found that some guys have issues with the frame cracking by just adding a spacer to the bottom of the stock mount. I want to add a solid rubber spacer to the top of the leaf spring clamp which on the front axle has a much thicker center section than the rear. do you guys see any problems with screwing a self-taping screw into the top of it?

I don't think I would use a self tapping screw but drilling and tapping it would be fine.