Installing a MOMO steering wheel on my 91 325i

[Cashmere E30]

My wife recently purchased a Momo Competition wheel from Pelican as well as the model 2006 hub adapter for me for Christmas. I had read on Turner Motorsport's website that for all cars with airbags, modification would be required. Has anyone performed this upgrade? I tried a couple of mods including additional washers, but the depth of the steering wheel seems to be off. With the nut fully tightened, the wheel can still move fore and aft. I have seen this reported on different posts. Any help would be appreciated.