Are you saying the ring doesn't fit over the key head? With the ring completely off, you should be able to turn the key, insert the pin, then put the ring over the key and the pin. If it doesn't fit, then maybe you have a nonstandard key.

__________________
Rick Miley
2014 Tesla Model S
2018 Tesla Model 3
2017 Nissan LEAF
Former MB: 99 E300, 86 190E 2.3, 87 300E, 80 240D, 82 204D Euro
Chain Elongation References