Would a 4 year college accept a GED as if it was a high school diploma?
Four year colleges do not take a GED as a diploma. If you do that, you will have to complete two years of junior college (and may or may not have to get an A.A. degree) before you can move onto a four year school. Why not just keep up with high school and college for your final year? I did that (took college classes at community college as a requirement for a high school course and also during summer school) and I knocked off about 12 units for when I went to UC Davis. You would be a lot better off to keep going that way.