You can try using this: www.dropbox.com/s/ohyzk4a58jrjxn0/Lucas%20Simpsons%20Hit%20%26%20Run%20Saved%20Game%20Editor.exe?dl=0

I don't think it was ever released because it was broken in some way, but I think it would it work for your needs.

Open your save file with it and change what you need to change.

I tried importing my save file but it just gives me an error saying "unrecognized file size". I'm not sure what that means, is there something I'm forgetting to do? Perhaps this is what you were talking about when you said that the editor was broken in someway? Or maybe my save file itself is somehow broken.

For reference, it is 8KB in size and has no file extension. Is the latter part normal for Hit & Run's save data?