You can find some Cushman information at the following site:
https://www.vintagegolfcartparts.com...l6500i741ilu1q
You can find the model number, year and manual information here:
https://www.vintagegolfcartparts.com...ence-guide.pdf
This manual confirms that the 898339-8910 is indeed a 1989 Cushman Courtesy Carriage (see page 29 of the guide).
Regards, 3CW