When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
305/65/18 are exactly 1" (33.6") taller and a bit wider. My 285 65 18 are about 11 1/2 to 12 " wide. My guess is the 305 will be about 12-12 1/2" wide.
Yes it would look good.
Just keep in mind about gearing. I have 3.73LS and I notice to loss in low end from 265's to 285's