Well, there are certainly large trucks pulling 2 trailers out on the roads. I’d expect to get stopped by every cop along the way, even if it’s legal, doing this with 2 cars as the towed objects. I’d ask your state’s highway patrol or DMV about if it’s legal. As for safety, I’d be very cautious and make sure to follow whatever rules may exist.
Sorry about overlooking your post. I was told several months ago that the fuel pump was on its way out, and I just wanted to see if there was a way of testing it myself before going to the repair shop.