dont listen to this guySR_Smith wrote:No! under no circumstances should you attempt to drill a new lug hole or enlarge existing lug holes.
There are so many failure horror stories in the industry, just reading your post gives me the creeps. Seriously this idea of yours is common, but quite frankly, horrible. Not your fault..
16.5 is fast being outdated anyways. Stick with a standard size and ignore those wheels, period.