2 thoughts this am for Monsieur Hair-ree and his Ongoing Scooby Shfiter Snafu...
1) are you SURE you got the right part from KB? Our KB short shifter had tha same size ball and same width pivot bushing as stock bits. We needed a couple spaces to snug up the bushing fit, but didn't have to spread the fork on the shfiter rod. So maybe got the wrong bit from KB? Worth a call to them with the part # from the pkg you received. if the KB part is wrong, even the new bits from Joel wont save your weekend.
2) you can get the car into gear with the shifter apart. 2 options: put stock shifter back in w/o circlip around bottom of plastic socket that holds the ball, actually I've been driving my street WRX this way for weeks now and if your mindful, it's no prob. 2--push shifter rod forward with fork aligned roughly where 1st would be in normal pattern.