We sell and install a lot of big wide wheels. 345s on 12" or 13" rims are the norm around here. Anytime you go over 10" wide your going to be forced into a cut and welded (widen) wheel to make a 11", 12", 13" in a 2 piece wheel. So it is always better to go with a 3 piece wheel in these applications. We have a few brands to pick from.
Here are a few size samples for you. You can see more pics and check out some cars with 335s / 345s on our site.
Here is a 345 / 25 / 20 on a 13" Forgeline SP3P wheel
Here is a 345 / 30 / 19 on a 12" Forgeline TA3P wheel
Here is a 335 / 30 / 18 on a 12" Forgeline ZX3P wheel
