It was a different part number mine was good till 2008 I ordered the truck today so I,ll wait till they call could be a couple mths then order the Torklift it sounds easier to install.
I put 2002 Torklift's on our 2008 Chevy. I found 1 hole on each side had to be drilled.
Wouldn't hurt to fit it in place. If a single bracket is different you may be able to use a spacer to make it fit or Happijac may sell the one that fits your truck separate from the whole kit.
This doesn't really help you, but the one I used on our 2001 F350 worked perfectly on our 2006 F350. I agree, checking the part numbers should help. You can also call Happijac and ask. I called them a few times and they were very nice and very helpful.