That looks like some kind or "universal" rotisserie setup, especially since the bracket has two mounting positions. The first thing I would do is either cut the very top of the bracket off so it lays flush against the cookbox or put some washers under the bracket for the same reason, get the bracket installed better. The second thing I would do then is look for a replacement spit. Rotisserie cooking is measured in hours, and if you don't have a properly spinning spit you will burn motors out quickly, and likely ruin more than one cook. Maybe even damage the grill itself. I would not modify the grill at all, and in fact Bruce and Larry's suggestion to do what you can to obtain a part number 9890 is actually the best idea for this conundrum. Ideally a kit with motor, bracket, spit and forks, but in New Zealand I'm not sure what is available. Perhaps others can chime in with aftermarket options that fit the 1000, and maybe you can order something that fits correctly. I just feel like you may go through a lot of effort only to eventually end up just getting the correct setup anyway.