Just want to throw in my $.02.
I installed my oil pressure gauge today using this DIY relocation kit. Worked beautifully.
The only hose they had at Home Depot was 18" long. Looks identical to the OP's pic though so i'm not sure if he was mistaken in his post on the length.
I say this because 18" is perfect, I wouldn't want it any shorter.
Just FYI if anyone runs into the same thing, don't fret, 18" works fine.
I Teflon taped everything and no leaks. I used the front galley plug under the alternator.