One here suggested to "drop in a 302". It isn't as simple as that. It requires a change in the suspension and many other components. I suggest either use the money to restore items on the car or if you want a V8 car, sell yours and get one that is already equipped with one. As far as technical help, get in touch with a local Mustang club. There are many all across the country. Members would be quite willing to help you.