What is your goal?

Since it's a custom job, there is no right or wrong where the rear axle rests.

If you want the truck to appear stock to the casual observer, then move the wheel forward of the wheel well centerline by 2 inches. That looks to be about 3 inches from where it is right now.

1950 Chevrolet 3100 (Ol' Roy)

1939 Packard Standard Eight Coupe (The Phantom) | 1956 Cadillac Coupe de Ville (The Bismarck) | 1964 Ford Galaxie 500 coupe |1966 Ford Mustang (Little Red) | 1969 Pontiac GTO (The Dishpit) I 1979 Ford F-100 | 1976 Ford F-150 (Big Red) | 1995 Ford F-150 (Newt)