In fact no problem to fix i am replacing the leaf spring and i have 2 new shackle from 2 gen. The rubber are the same diameter only the thickness is different.
The wider shackle can work but if there are any interference issues you wont know if it's because of the shackles or because your car is tweaked. Use the right ones. I have the wrong ones; and my car is tweaked.
Plus now we're all going to look under your car to see if it looks right (it only has to look right most times).
The wider busings will not work correctly. The front bushings cannot be wider because there is no room in the front perch. The rears can be wider but only if you use the top and bottom sets. Otherwise the shackles will not tighten up correctly. The less bushing shoulder you have the less flex you will get out of it.