Considering the age of the car I'd guess it's some sign guys interpretation of a serif typeface that he liked. Now, that doesn't mean it isn't based on a real typeface (notice I am deliberately not using the term 'font' here), but it looks more like it was individually done. Your best bet might be to go to one of the free font sites like DaFont or Abstract Fonts , type 71 into the 'Custom Preview' window and scrolling though until you, hopefully, find something close.
A E L seems to be a company that rents container trailers for storage. Again, from the looks of it, it appears to be hand painted.