OH FT:HELLAFLUSH "One Mad TL" VIP styled 1st gen Acura TL - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum
Here is some inspiration.
Generally, these types of car are meant for higher offset rims. An example is on a 02 TL type S wheel the stock is i believe 17x6.5 55+ offset. For the Legend, the stock wheels are 15x6.5 with a center bore of 70.3 (offset is prob similar). I am sure the stance would be very similar to the 99-03 TLs. I think the widest you can go is 19x8 but with a higher offset like 50+, 225/35/19 size tires. For more aggressive fitment 19x9, 235/30 or 35/19 with offset of like 30-40+ would work but of course you would have to do fender work (then you're getting into the very flush look). But it depends what type of style you're looking for.
For basic, 18x7.5 offset of 45+ with 225/40/18 works too. But more research the better. I have a 02 TL type S so i can't relate, but hope this helps.