Rotating axle hubs, help needed

[spudfan]

Regarding rotating axle hubs on the Guinness keg wagons and the fert wagons, where is the grease nipple situated? I'd like to give them a shot with the grease gun now and then to keep them running smoothly and quietly. I've checked the parts sheet but it is not identified on that. Anybody able to help?

[Broithe]

I believe that there was only ever one grease nipple for the models, and it is in China.