DIY & Home Improvement

OK, here's the back of the sink, with four holes:



It was handyman-installed years ago without bolts or brackets -- it was just set on the base and siliconed to the wall. I've decided to do it right. Or attempt to do it right.

I'm Googling like mad, and believe I may have to do something like this:



Or use drywall anchors? Drywall anchors don't seem as sturdy (this sucker is heavy)...what do you think?

Next dumb question: It looks like I can reach only the two center holes on the back of the sink with my hand or a wrench. Are the two outer holes just to "lay" the sink on some sort of a bolt for additional support? Something that may look like this?



Thanks for any help...I'm determined to do this!