The Owner's Manuals for my former People S200 and People S250, stated 91 Octane, the same as my GTi300. However, this is NOT for US Octane, this is for Overseas Fuel. For the US, our 87 Octane, is their 91 Octane. Just use Regular 87 Octane Gas, and it'll be fine.
May want to consider adding Sta-Bil or Star Tron to your Fuel, in case you get Fuel that contains Ethanol. That stuff can gum up pretty quick! I use both Brands. Doesn't take much at all. I do it every Fill-Up.
Best of Luck & CONGRATS on getting it tomorrow!
Cheers!
BB