Mine are ready for flight testing tomorrow. The original 3/4" wide wood skis just dug into the snow so I've added 2" wide plastic shoes to them, cut from a milk carton:
I also did away with the two music wire cross pieces, which, upon further reflection, probably really didn't do anything useful. Plus they cracked off when flexed

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Here is the view from the underside, showing the spring's (adjustable) velcro mounting spot:
And here's the tail skid ski:
The wire skid is sandwiched between two pieces of velcro - easy to adjust the angle of attack and move from one plane to another.
Taxi tests in the back yard (with two different planes) were a success! The weather is looking good wind-wise tomorrow - I'll report back