The Mk 2 Home Gardener was a complete redesign, using metric dimensions all through. The original Mk 1 was all done in Imperial dimensions, i.e. an 'inch pattern' design.
So it would be no surprise if the Mk 2 was designed around the OHV Briggs.
That said, it might be possible to modify a Mk 1 for the OHV engine, but you'd need to have some design and fabrication skills - not a job that would be worth having done commercially.
Cheers,
Gadge
"ODK Mods can explain it to you, but they can't understand it for you..."
"Crazy can be medicated, ignorance can be educated - but there is no cure for stupid..."
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