Or, swap the male and female ends. I've done this for years with a small fiberglass indicator rod, male is fixed, female mounted on the rod. A threaded nipple in the male end with a galvanized NPT cap to tighten it on the angle iron support keeps it in place. Drill a 1/4" hole in the cap for dirt and dust drain. A plumbing compression sleeve fits the bigbox store fiberglass driveway marking rods, and holds the rod securely. I'm not where I can take a picture of the assembly, but if anyone is interested I could get a couple this evening.