I don't know anything about the power steering but what I can say is, with the engine, I would remove the shroud, flywheel, PTO, coils, and any other wires I can. Then make sure to block off the intake, exhaust, and spark plug holes, as well as any oil fill or drain plugs. Also if you can find it
the crankcase breather.
I wouldn't want any water getting inside that engine, but still want it to all be clean, so be sure to block off ALL possible ways that water could enter the cylinder or crankcase.
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'70 107 with k301 engine swap
'71 106 with 38" deck
'70 147
R with factory replacement k321, 42" deck
'61 Original with 38" timed deck
'63 70 "pinkie"
1863 with 54" deck
'46 Farmall H, '50 Farmall Cub
105 x2 (parts)