GT XCR frame shock bushes

[lee51428]

Hi

I’ve got myself a 1999 GT XCR 4000 which I’m rebuilding. It came with a random rear shock attached but I’ve managed to get the original one. My question is should there be some sort of bush on the rear triangle where the shock attaches as the hole takes an m8 size bolt but the shock is m6.

Thanks in advance for any info.