Yeah, MT's are great in any size just about. But even you admit not the best for DD.
I am telling you, if you could run even 315's in the rear and 275's in the front you would see a world of difference. 19's are tough to get really good performance out of them. They were never designed to BE a performance tire. Just looks.
So many guys fell in love with them that performance designs sprang up out of demand. This is happening to a lesser extent now with 20's.
Eighteens still remain King for performance design. When using 19's. the profile must be so low (to fit) in a stock E46 M3 that you have almost no side wall that can compress for traction. You end up with "o rings"..LOL. Not really, but...
If you GO WIDE..really wide, you can pick up so much that is lost in traction from the low profile 19's. And go soft. The A-6's are EXPENSIVE, but they dont have that TOO squishy sidewall like the MT's and they are definitely STICKY.
Bottom line: If you insist on running 19's and want to NOT waste all that HP you paid for, then its gonna COST you more $$ than running 18's or 17's.
You need soft and wide and decent side walls.
R888's are fine, but would be MUCH better in 315 or 345 like Maverick.
Why not try a huge trim and fender roll? Or BEST bang for the buck a whole new welded in flare? I think HPF is coming out with flares that weld right in...well sort of.
That is going to be MUCH more cost effective than a custom job.
You HAVE those nice WIDE wheels that cost a fortune. They are BEGGING for WIDE RUBBER!!! Give it to them. Seriously. They will love you back!
OMG! Elevens and TWELVES! It is almost criminal not to be rolling on some huge rubber meat. And yes, it is bitch to get them to fit. But its done all the time.
Go back and print out the photo of Maverick's tires and put the photo on your wall or bulletin board at home and at work. I would give you less than a week before you are on the phone to your body shop.
EDIT: Did you change the title? I swear I dont remember seeing "wide body" in the title before. You dont HAVE a wide body car yet as I recall. If you did, you would have no fitment problems.