For a veggie garden, why not a PTO tiller instead. No bottom plow nor disc harrow needed.
I'll be using my disc harrow with the YM2610 for a few more years. Woods turned to pastures and garden plots. Never needed a bottom plow. Just added enough blocks atop of the disc harrow and it did all the work.
Your machine has the 2T90 engine. It's much like the 2TR20. Not sure why Yanmar had 2 engines in 2-cly series with the same ratings.
BEFORE it looked like a garden ....
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