This will give you a clean cut through the siding.
Attach hose spigot to siding.
That way you wont ruin your sideing for a hose reel that will likely fall apart in a year.
There are at least three alternative ways to do it.
If you need more width to the post just get a 4x8 or nail a cross piece of 2x6 to it before you hang the reel.
If you are using a mounting block you will need to cut out for the block and then pull back the siding to get the backing plate installed.
Hold each piece up to the faucet pipe and mark with a pencil where the pipe will pass through the.
This renders the siding vulnerable to moisture and voids the warranty even if you seal the hole.
From outside use a hole saw to drill for your new pipe.
The connector on the short hose twists onto the threaded end of the hose bib so the hose reel is installed close enough to.
Cut the siding into two pieces if the faucet will be located in the middle of a piece of siding.
Find location inside of house and drill a 1 4 inch pilot hole from the inside through the siding.