You might want to get a 250 ML graduated vessel to compare injectors. Home brew supply shops have them. I built an air powered test unit set to 35 PSI due to not wanting to blow up my workshop. On the advice of a local injector workshop I use lacquer thinners to clean the injectors which is a lot cheaper and more effective. The vapours however do melt some types of plastic for example the lid of my sonic cleaner which did eventually solidify. I would remove the pintle caps, filter screens and "O" rings if using thinners. The thinners did however restore a set of Ford injectors that nothing else would clean and had been rejected by another injector shop.
Regards Martin.