[djnolan]

You have to take the injectors out of the car either way.

I would take or send them to a place that has the proper equipment to flush out, rebuild, and flow test them. The power and health of your engine may depend on this. You don't want uneven fuel causing uneven wear or poor power.

PS. Also change the fuel filter at the same time. By the same token, injectors have replaceable micro screen filters that build up sediment and should be replaced during the rebuild. There are also several o-rings to replace.