G'day Axel and welcome.
The C10 (Concours/1000GTR/ZG1000) uses different carbs and cams to the ZX900/1000 (GPZ900/1000RX). You can swap ZX1000A1/A2 (GPZ1000RX) cams in and fit the 36mm carbs but the power gains are not enormous and you lose the low end grunt of the C10. In good running order the C10 should deliver 108bhp at the crank but with shaft drive that gets reduced by 15% to around 92 at the rear wheel. It's enough to take the bike well over 140Mph but if you expect to get ZX11 type power and acceleration, then you'll need to go the turbo route. Although yours is a 99 bike, it is an 85 design and the engine was pretty much unchanged from 86-06.
A few people have done turbo C10 conversions but I don't think any of them lasted very long. I'd love to hear otherwise.
Since the advent of the C14 (Concours14/1400GTR), getting one of those is a much easier way to get a ZX11 fast (if not faster) sports-tourer.
Useful sites for parts are eBay, your local Kawi dealer and
https://murphskits.com/kawasaki/c10-concours-zg1000/If you need a part that you can't find locally, ask on here as some of us have C10 stockpiles.
Just don't ask for footpegs or mirrors.
Looking forward to seeing pics of her.
Good luck.