I just noticed the 4 bolts that hold that hatch on at the top of it are all rusted up but had a plastic cap over them. anybody replaced these before or are theybeven replacable?

 

You can pop them out one at a time and replace them without upsetting the hatch alignment. New ones are available through Hawks or Modern Day Muscle. Another good option is finding non-rusted used ones.

 

If you found a set at the junkyard, you could send them to be powdercoated and replace them one at a time.
As was said by "naf"

 

mine are rusty as well and when i attempt to loosen the nut the whole bolt spins. How did you get yours out??

 

If the whole bolt is spinning, the only way I know how to get them out is do this: use masking tape around the glass and carefully grip the edge of the bolt with a pair of vice grips and with your wrench or socket underneath, slowly turn the nut. The vice grips will damage the plastic coating on the bolt, but if the bolt is junk, it won't matter. Being as it spins in the glass with the nut, the bolt is junk as the hex portion in the glass has rusted almost round allowing it to turn. When you get new ones, they will have a nice hex formation that prevents it from turning while you tighten it down. As someone else said, do one at a time.