UK owners of Suzuki's know that Suzuki UK (or EU?) won't sell you a Service Manual. I found one US dealer that had the US (duh!) version but wouldn't ship to the UK so I kept looking...
... this dealer will ship to the UK (and takes PayPal or cards):
store.schnitzracing.com
I don't know all the differences between the UK and US versions - I've noticed the tail lights are different and I think the US version has LED turn signals as standard and I'm guessing the front ones light up as running lights? I don't imagine there's any fundamental differences though.
Be advised if you order a manual, the cheapest shipping is $50 so the bottom line is $140 (about ÂŁ106 - pound is doing well against the dollar at the moment). I shouldn't get hit for import duty I think that comes in at ÂŁ135.
... this dealer will ship to the UK (and takes PayPal or cards):

OEM Suzuki GSX-8S Service Manual (24-25)
The OEM Suzuki GSX-8S Service Manual (2024) provides factory-level service, maintenance, and repair procedures to keep your GSX-8S running like new — straight from Suzuki.
I don't know all the differences between the UK and US versions - I've noticed the tail lights are different and I think the US version has LED turn signals as standard and I'm guessing the front ones light up as running lights? I don't imagine there's any fundamental differences though.
Be advised if you order a manual, the cheapest shipping is $50 so the bottom line is $140 (about ÂŁ106 - pound is doing well against the dollar at the moment). I shouldn't get hit for import duty I think that comes in at ÂŁ135.