NOTE: changed the color of one arrow. Colored it incorrectly the first time
What's the time frame of the twisted hoses?
Of course few if any 65-66 Shelbys today have their original heater hoses in place and untouched
Looking at my pictures and focusing (as usual) on original examples and period pictures I found the same twist on cars from the carry over period (so from lvery late 65 production) though 1966 GT350's in the 2100's. Wish I had more examples to compare. In at least one case the original hoses may have been removed and reconnected to the intake and water pump yet the lower hose still appears to have retained the twist in the hose as it lays in the valley between the intake and valve cover
As a reminder for everyone originally (in 65) Shelby was swapping things like intakes at their plant. In an agreement with Ford San Jose started to install the intakes leading to a couple of short run differences (painted intakes on a few engines) before they got things dialed in. This transition between who was swapping the intakes took place during the period late 65 San Jose production when they assembled what would become the early (carry over) 66 GT350's. This period may be related to that picture of all the V8 engines at the Cleveland plant waiting for shipment we have in the Plant section of the site.
Would be interesting if we had enough period pictures of non-Shelby engines from the period to see if this was a common practice across the Mustang
A picture of the latest built 66 GT350 I've got - reported to have been taken in 1966. Appears to be the same twist in the hoses