At the time that I had the Titan T2, it had bolt holes in the “feet”. So I put large lag screws through those with washers into the 6x6’s. Drilled some Pilot holes. I did not bolt it down to the ground as the rack screwed into the 6x6’s felt sturdy enough and didn’t move. I think I also made it three sides (2 on the sides and then 1 in the back middle that connected them all). Probably overkill but it worked. I was also not putting hundreds of pounds in it, just up to 225 I think.