The Rieco-Titans on my 2001 Hawk are the c-ring ones. Those came with it. I used them to load the camper onto my older (2001) F150 by bolting them directly to the camper's jack brackets.
When I replaced the F-150 with a 2013 Tundra, I added 1/4" aluminum extension plates. I don't quite remember whether I HAD to have the plates or just wanted additional clearance.
Note: My Hawk has the older jack brackets (the one-piece, 14", five-hole ones) but I believe the jacks should also work with the newer brackets (the two-piece, 13", three-hole ones). (And I see the ones in the manual are the newer style two-piece ones.)
Edited 10/31/22 to add:
Update:
This morning I noticed the manual shows different part numbers for jack brackets for fixed versus c-ring jacks. Does that mean the c-ring jacks ONLY work with the brackets with the c-ring part number? Or will they work with either?
So I called Rieco-Titan Products in Frankfort, Illinois. According to customer service agent 'Sue', the c-ring jacks will work with either bracket. The different part numbers have to do with the type of hardware included with the bracket ordered under those numbers.
Edited by Old Crow, 31 October 2022 - 07:59 PM.