This isnt exactly fine woodworking but it might involve power tools so
I figured I ask here.

I am remodeling my kitchen which required me to move a window. I am
now at the point where I am trying to replace the siding. The house
was built in 1957 and has 1 x 8 redwood board and batten siding.

I figured I'd just go and buy more of the same at the local lumbar
yard. Nope. Somewhere between 1957 and now, the thickness of 1x
redwood boards changed from 3/4" to 5/8". So all the new stuff I can
buy is an 1/8" short and doesnt match with the old siding.

Can I buy an 1/8" thick sheet of something that I can put in back of
the boards? Can I plane down a 1/4" thick piece of ply to use in
back? Use 1/8" shims and leave a space behind each board? Can I
special order the right thickness? (Though I dont think the local
lumbaryard is equipped to do that)

Or should I just go out and buy 1 x 8 pine boards and hope it lasts?

BTW, the house is painted (the previous owner painted it, not me) so
pine would work just fine, if it would only hold up to the elements.

I'm tending toward the pine.

Any other ideas?

dickm