I love the sound of the Seymour Duncan Firebird pickups, but I can't work out what type of guitar I could fit them in without having a massive headache. I'd love to get these into an SG body, but I fear it would be a lot of effort that I'm not equipped for!
The pickups in the classic Gibson Firebird are known as "mini-humbuckers". You can buy adapters to replace the full-size humbucker mounting rings used by many guitars, including most SGs, that will allow a mini-humbucker to be used instead. As this just screws to the top of the guitar in place of the previous ring, it's a reversible operation that won't cause damage.