Did you get the VCM version or normal?
You must replace the delxuo .dff and the deluxo txd with the ones included
Now you best bet would be to download the Vice city mod instaler
Vice mod installer
and if you do not have this you may want to get it.
Now, with the mod installer,It requires the codes for the files that come in the Readme File.
Be sure to check and double check to make sure you have done it right
ok open your mod installer, then go for your mods readme.
then find the car you want to replace, which will be the deluxo.
Then get the txd,dff,and handleing data from the read me and put it in the correct lines..
then click instal mod, and if all went well you should be done....
I hope I have been of some help to you and if you have any problems or questions feel free to pm me.