Steering column grommets

I purchased these two rubber grommets from SNG Barrett for my 1950 XK120, they are shown as correct for my car, the round one fits on the firewall but I can find where the larger one goes?

If you have the roadster, then it’s the grommet only. Fixed head coupe? Then you want to use the larger one.

Mine is a roadster, thank you so much @Christopher_Potempa! Not sure why they are listed under the same part number for a roadster!

Yes, the long one is for FHC and DHC.