CYPD3120 firmware project is still available in SDK3.0.2. You could get it firmware project from the link: https://www.cypress.com/documentation/software-and-drivers/ez-pd-sdk-v302-ccg2-all-applications-ccg3-cable-adapter
If you have been installed it, you are not need install the SDK again. If you cannot be installed, please kindly let me know the screen shot of the error.
Meanwhile, the SDK3.0.2 using PSoC Creator 3.3 only.