Those will not work, they are from an '88 or newer pickup or '92 or newer Suburban. You are correct about the backspacing.
Just a side note, I noticed the term "offset" being used. While not totally incorrect, the correct erm would be "backspace". Offset is the dimension, +/-, from the wheel centerline. Backspace would be the measurement from the wheel mounting surface to outer edge of the inside of the wheel. Offset can be affected by the combination of backspace and wheel width.
