The new hose just landed on my doorstep after completing it's 9700 mile journey..
It's 37", exactly like the one I have!
Dammit!
37" is what the V8 application uses, somethings not right.
Maybe the brackets on your underdash unit aren't correct
so the unit is not as close to the firewall as it should be
making the hose too short.
I measured the new hose I bought from NPD for my 6 cyl
and its 52", thats another option for you, part number 19867-1
I would try hooking up the 37" hose with the underdash unit loose,
not bolted up and see where it ends up.