In naive theory, min+2 because there are two cycles the custom glyph isn't spawning an earth (from what I heard about OC and OR this isn't capable of double spawning). One is an extra grab for wands and the other is not entirely buffered up for last-salt latency. Both are things I'm like "uh I don't want to think about attempting it" and could be quite similar to Probe Module P4 in the "if there's a will there's a way" sense.

The arm 1 wanding setup and arm 4 two-and-one wand initialization feel quite low-effort, like I just try at something and quickly found one way it's working. Therefore alternatively this solve could be titled "just some fast kludge". Concretely the pistonness of arm 3 and the duplication glyph to paint arm 1's wand back and arm 4's track have much potential for cost savings.