I always thought Andrew Probert designed the refit. Anyway, the nacelles look nearly identical to the locomotive, and I hardly think it's a coincidence. I don't know if it was ever acknowledged in print.
If I recall correctly, Matt Jefferies had already done some preliminary work for a new Enterprise
back in the mid-1970's before he embarked on another project (as Paramount couldn't decide whether to greenlight a new Star Trek television series or not).
It started something like this
. If there's enough evidence of an evolution in designing the new nacelles, it could be a coincidence. Of course, Matt Jefferies might have seen this locomotive and subconsciously remembered the design when he started on the new nacelles (it's called cryptomnesia
Indeed, the locomotive looks a lot like the new nacelles, great find!