Bought some big wheels, worried they won't fit, l700

Try this link. I posted up some pix of 15x7.5s +25.
Yours will be about 22mm narrower track. (Further in) about .9 inch.

With a stretch tyre and some bolt on flares they could maybe work. You should have enough on the inside to clear the spring base plate. Will scrub on full lock though. The guard rubbing will be as much as you can put up
With I guess. Just watch the walls for wear.