wrote

would be a lot of work and expense. What I was thinking instead was
to cut off the bottom 12" of the siding with my circ saw. Then stick
some z-flashing up there, nail it in through the siding panels, and
then stick a piece of 5/8" 1x12 hardiboard (or equivalent) under the

Yes, it will work. You just need to create that gap above the water area.
The same fellows who vinyl sided my house did a 'patch job' down the street
much like this. They did it with a contrasting vinyl and matched the upper
trim work discretely to it and it looks very very nice. Done almost 10
years ago and looks like new.