Here are a couple of options for you:
You can use Tiermann Auto Installer. You can install it into the ROM with a kitchen or you can run it manually if you want. Most kitchens have this as an option. More info -
LINK
Another option is to make your ROM UC (User Customization) compliant. More info on UC here -
LINK
A user here made a mortscript autoinstaller. More info here -
LINK
I had used Tier's with my own custom mortscripting for a long time and recently moved to UC and still use my custom mortscripting.