I also worked full time throughout my prereqs and did not have evening classes available, but I switched jobs so I could work about 3 a.m. to 11 a.m. depending on my semester schedule, then take my classes in the afternoon. Fortunately, I had a flexible boss who didn't care when I worked as long as I completed everything before daily deadlines.
I did have a few morning classes that were not offered at any other time, and then I'd start even earlier, rush to class and rush out and finish my work on my laptop before deadline. It was a pain in the butt, and my GPA for my morning classes is likely slightly lower than my GPA for my afternoon classes, but you do what you have to do.
There is no way I could have completed my prereqs at my previous job, where my schedule was entirely at the mercy of the news.
So I think it does help to think outside of the box. Maybe your current job won't work, but is there another position within your company or field that would?