Tire Size Sanity Check

[lt2mc]

A question for all my esteemed colleagues in this forum. I am getting ready to purchase a set of tires for my e70 3.0si, and I thought I would have some fun. I live in Colorado and do a lot of mountain driving, so I thought I would go with a set of Goodyear Wrangler Duratecs (265/60r18). Currently I am running 255/55r18s on stock wheels. All my research here and elsewhere indicates the 265 combination should fit. Before I pull the trigger and drop $1k+ on new shoes, can anyone here convince me that combination won't work?

BTW, I am investigating purchasing a set 15mm wheel spacers just encase my top front ball joints becomes a problem.

Thanks in advance for the advice.