i found some wheels i like for my gxl and they are 17x7.5 and the offset is 45mm and wanted to know if they will fit and what size tires can i use but i know that i should use something like a 35mm offset but these wheels only come in 45mm

 

I don't believe so. It might but won't be a good offset to run. Your wheel track will be pretty narrow. Are you looking into Rotas out of curiosity?