Where is the best place to install an inline fuel pump on this vehicle?

I don't think you can, you will need the inline pump to pull through the old pump in the tank, you will be better off replacing the pump inside the tank. Here are instructions on how to do it in the images below. This generic guide can help you see what you are in for when doing the job.

https://www.2carpros.com/articles/how-to-replace-an-electric-fuel-pump

Check out the diagrams (below). Please let us know if you need anything else to get the problem fixed.