It appears you have been misled.
What version are you talking about?
......because......Pinks cannot be substituted for yellows. They are completely different in configuration.
Early STi (version 3/4 & 5/6 all have yellow side feed injectors)
97 & 98 WRX have grey side feed injectors (380cc)
99 & 00 WRX have the same yellows as the equivalent year STi
01 onwards WRX has blue top feed injectors
01 onwarsd STi has pink top feeds.