Defroster hoses

What I meant by "slightly smaller" heater outlet was in reference to the 2.5" hose.

So, on the driver's side vent: 2.5" hose from vent down to 2.25" outlet on box (which, if I recall, is also on the left). It's not a tight fit but pretty good by itself. The ribbing on the duct hose creates the interference.

On the passenger side: 2.5" hose from vent to adaptor. 2" hose from adaptor down to 2" outlet on box. Nice snug fit.

I used nylon ties on the vents and adaptor to hold everything securely.