Wondering if the Rambo large rack is something that you can use other than the rad rack link below.....
https://www.opticsplanet.com/rambo-bikes-rambo-rack-large.html
I will assume you are referring to the rear of the bike, since the rack you linked lacks the four holes to bolt up to the head stay in the front of the bike. I'm sure it's possible to use this rack on the back, but with no mounting holes, you will be forced to rig up mounting brackets. It seems a lot easier to buy a rad rack.
The large basket from Rad also doesn't mount to the head stay. You have to buy the flat rack and then mount the large basket to that.
I bought the small basket for the front of my rad wagon and absolutely love it. We have a caboose and one yepp seat in the back. But I also have put a milk crate back there and had it attached to bike via bungie cords and that worked great. Got several bottles of milk and beer in there and felt very secure.
okobojicat i agree with ya, my new RW will be her Monday and I did get the small basket for the front but looking to get some sort of cargo for the back. I may have to get creative for mounting