jdi/nwds upgrade

HI,

I am planning for an upgrade of jdi from sp12 to sp13. does that mean that to deploy the new .sca files on top of the existing one. or should i remove the JDI sp12 and isntall sp13.

same with case of NWDS.. i have nwds sp12 with many projects. if i upgrade my nwds to sp13.. are my projects gonna be there or not.. is there any way that i can take a backup of the projects that i developed and run the upgrade..

could you please help me in this regard..sorry if the questions are silly...

thank you