Replacement of 8.75 axle

Gentlemen,
Its been a long time but I think I'm finally back to working on my cars. I'm a little older and the memory is starting to go. I need some help. I removed my rear axle to replace the wheel studs and then I attempted to put back the axle. The axle seems to go all the way in but I cannot tighten down the flange to the backing plate. I am about 1/4 inch to 1/2 away. If my memory is correct? you just insert the axle in any way and it should work. I do have the green bearings so no adjustment necessary I think? What am I missing? Why isn't the flange flush? Help?

Thanks