the GC and koni is one clean setup. Its just like the Koni "sleeve" coilover setup. GC, has a special adapter that fits directly to the C-ring on the Koni yellow shock. For others like KYB, you have the Sleeve coilover setting on the shock's perch. If you want the sleeve welded to the shock, then you'll have to purchase full coilovers... if you think about it, GC+ Koni Yellows~$850, full coilovers ~$950.