I tested a set of 8 for two different Chevy engines. One was a 1996 454 where they are buried inside the middle of the intake. The other was an LT1 350 Chevy. On the 454, once the top half of the intake was off you could see which ones were leaking by energizing the fuel pump and watching for which ones either sprayed or dribbled. On the LT1, 8 small glass jars, one under each injector with the sets pulled out and crank it then see if any were dry and any dribbled.
If your engine doesn't have the retaining clips for the injectors, many vehicles do and you should be able to find some.
Bill AKA "LOBO"
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"Getting old is inevitable, growing up is optional"
Darth Vader 1986 F350 460 converted to MAF/SEFI, E4OD 12X3 1/2 rear brakes, traction loc 3:55 gear, 160 amp 3G alternator
Wife's 2011 Flex Limited
Daily Driver 2009 Flex Limited with factory tow package
Project car 1986 Chrysler LeBaron convertible 2.2L Turbo II, modified A413