Is the concrete 6" or the whole is 6"? If the concrete is 6" you can buy special drill bits at your local hardware store to drill. It would help if you had a hammer drill as well.
I have a concrete porch with one step. The concrete that is verticle between the step & the porch (riser?) has an open ( about 2in.) hole in it where you can see ...
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Is the concrete 6" or the whole is 6"? If the concrete is 6" you can buy special drill bits at your local hardware store to drill. It would help if you had a hammer drill as well.
https://www.bobvila.com/articles/how-to-drill-into-concrete/#.WT_anWjyvIU
Masonry bit