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If your friend's friend does this quite a bit then he may know were to put your mounts. Go visit the welder and find out what he needs to know before he starts on your frame. He will at least want to know what type of front end you will be using (suicide, spring over axle, etc.), what engine, transmission and rear end and what body will you be using. He could build you a generic frame with a specific wheelbase and you will later decide how and where to place your body. Not such a good idea. Go to a few rod runs and car shows and take pics of the rods you like. Go to your local library and read a couple of How to build a hot rod books. Check out some magazines and purchase a few that cater to the type of car you want to build. Decide on your suspension, drivetrain and body before anything is done. It will make it easier for you to build your rod in the long run. Good luck.