75mm can handle up to a 12mm spacer safely. Make sure you install the studs correctly and use loctite and never-seez as recommended.
In order to cover the entire stud, a 40mm lug should be used. A 34.5mm lug will leave a little bit of the stud exposed. It all depends on the look you're trying to achieve.
Here is an example of a 40mm lug that I've used before:
http://www.evasivemotorsports.com/mm...tegory_Code=L1
Also, remember that a spacer will change the length of the stud that will stick out, so a 30mm(ish) lug with a 10mm spacer may be sufficient... Just have to do some trial and error and/or take some measurements.
Oh, and I would get open-end lugs, unless you know for sure it's going to clear the end of the stud. Would be a major headache.