I usually use a syringe barrel and pressure can to clean injectors but just found this on ebay which should make it a bit easier.
Injector cleaning kit
I'd swap the 12v battery clips for a 9v battery connector with a push button 'momentary' switch.

I am in no way recommending that you use my method. However I have had good results cleaning my injectors using a $20-30 Aldi ultrasonic jewelry cleaner. I fill it with injector cleaner and cycle the injectors with a 9v battery and long long leads, I use extreme care not to create any sparks. Cleaner + Sparks = Bigga Boomba.
Regards Martin.

Thanks Holister, I've ordered one just to see what they're like.

Agree with the 9v and the switch.