I ran 26x9 hoosiers on my car with 15x8 rims. Looked better than the 15x8.5 slicks I've also ran. Very happy with the Hoosiers, I would recommend them.
The 26x10 slicks on 15x8 rims should fit and look a lot like the 26x11.50 ET street many people run.
1989 LX 5.0 - AFR 165 heads, FTI cam, ported Edelbrock Performer, 70mm TB, Tweecer R/T, 306 w stock crank/rods and Ross pistons, MAC 1 5/8 long tubes, Lentech Strip Terminator Lockup and 3800 stall, 3.55 gears, Zex 125 shot
Running on E85