I have a 99 Civic Ex that currently has Tokico Illuminas and rusted up springs on them. They still work perfectly fine but looking at upgrading to Ground Control coilovers for height adjustability in the winter. I'm not sure how old the Tokicos are, so eventually I am going to upgrade to Koni Yellows. I know there is a difference between the 2 versions of the coilovers. I've looked for an answer but can't find. Can you purchase the appropriate sleeves for the Konis other than buying a whole new set of coilovers? The current suspension came on the car when I got it.

 

I think the diameter of the sleeves are different.

 

When I tried, ground control wouldn't sell me just the Koni yellow style sleeves. That's all you'll need is the sleeves. The springs will be the same as the tokico style.

Just buy it at once. THmotorsports is a honda tech vendor. They sell them in the marketplace for cheap.