Hi Martin,
I have the same kit for my 12" SIP. I think they cost about £45 (mine came with the saw).
You are right they do fit onto the cabinet legs. Two of them fit on the rear, and on the front of the saw you bolt on a steel plate, which attaches between the two legs, and onto this you bolt a hook.
The final part of the kit is a long metal bar with a T handle on one end and 2 wheels and (something like) a tow bar mounting on the other.
When you want to move the table you simply connect the hook to the mounting, press down and tow it along.
IMHO the only pain is the 2 legs on the rear which stick out a bit to far and if you are not careful you could trip over them. This will not be a problem if like me if have the rear extension table (or build a run off table) because then you would'nt be anywhere near them.
On the other hand the good thing about this kit is that it allows the table to sit on the floor when not in use, unlike some after market ones which because of the way they are fitted keep the machine off the floor and often allow it to move when you are feeding the timber into the blade.
All in all it is a good kit and is certainly worth the money.
I tried to include a photo of the kit but for some reason I cannot manage it. In fact for the last week I have been trying to upload some pictures for the review I am doing on my saw, but despite reading Adams thread it just does not work. Theres nothing wrong with the instructions, its just me. Can anyone help?
Cheers
Mike