Did you try and turn it backwards because that is what I would suggest if the starter is suspected. You can also unbolt the starter and pull it off and then see if you can then turn the engine over.

1951 GMC 1 Ton Flatbed -- It is finally on the road and what a great time I have driving it!
1951 1 Ton Completed

My Chevy Master 4 Door is on the Road!