It shouldn't be too complicated as others have said. Just take your time and pay attention to how things come apart. If it is a direct replacement it should be easy.
One tip I'll add, use the original screws when reinstalling the new bridge unless they are damaged somehow. When you go to thread the screw in the hole, slowly turn it backwards until you feel it fall into the thread, stop immediately and start threading the right direction. This will help you find the existing thread and hopefully prevent stripping out the hole.
If you run into problems or have questions just come back over to Talkbass and ask for help.
One tip I'll add, use the original screws when reinstalling the new bridge unless they are damaged somehow. When you go to thread the screw in the hole, slowly turn it backwards until you feel it fall into the thread, stop immediately and start threading the right direction. This will help you find the existing thread and hopefully prevent stripping out the hole.
If you run into problems or have questions just come back over to Talkbass and ask for help.