Enough room for 15x10 on a Demon?

No room for a 295, it will rub the springs and the quarter lip, nothig modified, however im running sbp rear and using one inch billet adapters to lbp. The spacer gives me perfect offset to center the wheels in there and run a 275.

Do you have,on your car,the offset springhangers? Those will move the springs over to not be an issue; but then the inner tubs will be.Those hangers will allow about 15 more mm on the inboard side. And it looks like you might be able to grab another 2 or 3 on that same side as it stands. So now you would be at 275 + 15+3 =293. This leaves just a little trimming, rolling, or bending of the outer lip. Having said that, OP look up into your tub and notice the step that the inner tub has just a bit higher up there than the opening. So just because the tire is in there, doesn't necessarily mean you can drive it.If your ride height is too low, the tire will hit that step on nearly every bump, and forget about passengers, or using the trunk. So be careful in what you wish for.
Well positioned 275s on 8s or 8.5s are safe.