Yelmer: 1966 T-400 auto vac modulator?

[HOTFUN]

Posting a picture of a NOS Delco turbo 400 vac modulator that I replaced in my 66 swb when rebuilding the April 66 original 400 from my 66 c20 parts truck. The one I removed and the nos Delco service part both had the vac port on the front side of the can and my factory vacuum tube also fastened to accompany the hose connection. Since dual exhaust was not an option until 67 models( ignore my modification) was there not enough room for the rubber hose to get around the heat of the dual pipes and the port moved from the end to the side to tuck the side of the transmission? Interesting as I have collected several nos blue Delco #3027222 mods and just noticed Yelmer's beautiful restored 1966 chassis with the other style port modulator. Maybe a production change? Mark