Alexander Motors Inc Trenton NJ

I actually have quite a bit of knowledge about Alexander Motors because I own an Edsel that was purchased there. I have advertisements that they placed in local newspapers, and I was present with my parents on the day my Edsel was purchased. I have memories from that day even though I was only 5 at the time.
They went out of business in the mid 1960's--guessing around 1964.
When we were there in November 1959 they sold Mercury, Edsel, Lincoln, Renault, and Pugeot.
I know that I am basically three years late in getting this answer to you, but I just found your question today.
The building still stands. It is a Comcast office now. There is a place in the back of it where the stucco they remodeled it to have is broken and you can see the original brick of the dealership. I have an artist rendering of the dealership from one of their ads and a photo of a trunk slug they affixed to another vehicle (not mine. My father didn't allow advertising on our cars).
If you are still around, and still want to know more, send me a message and I'll come back to this forum to share.