55 gallon drum (plastic) planter handle

I recently found some cheap plastic 55 gallon drums on craigslist. I decided to use several to plant vegetables. I cut slots out of the sides of the planters, but the cut into my hand when I try to move them filled with soil. I designed these handles to fit in the slot. Dimension of the slot: I drilled two 1" holes 3.5" apart and 1.5" from the top of the planter. The handle is 3.5" long and angled slightly to curve around the 24" diameter planter so that it naturally fits. Use two .75" long scre