I do recall the Nap-a-Nee building from trips thru Napa Co. to Lake Co. in the '40s.  My first thought is that it was out of town to the north and if you ask Google correctly it will show "Union" where Trancas crosses present 29.  Now it gets hazy [I have a photographic memory but the fixer is shot]. I recall it on the inside of a bend where the northbound hangs west and was out of town. If you ask Google nicely it will show "Union" where Trancas hits present 29. I believe that Main St. was 29 at the time and it cut west somewhere to the present alignment; that may be the location. That was quite a drive in the 40s at 35 or so mph.  Much was what we called "ramshackle" but much [can't say if it was most] of rural California was the same. It bothered us not at all. Now I look for it. cheers, Gard English doesn't borrow from other languages. English follows other languages down dark alleys, knocks them over, and goes through their pockets for loose grammar.     —Unknown