The boat pretty much straddles the cradles -
so> TI is 18' long (216" - less 67" = 149") divided x2 = 74.5" hanging beyond the cradles front and rear - approximately
I tried using two cradles for my TI at the recommended spacing of 67" and I found that this places the cradles under the soft underbelly of the TI and in only three months from new, it has started to show a definite indentation where each cradle was located. Sorry Mat Miller (or Jacques who posted this spacing?) not intending to give you a hard time, and I know why this spacing is the same for trailer fitting for AI and PA, but it is not the best spacing for support of the much longer the TI.
I have to also say that the quality and fit of the new plastic TI cradles is in my opinion sub-standard compared to the older fiberglass cradles I have for my AI. They have already started to show cracks on the outer aka support after three to four month use from new.
I have moved the front and rear cradles out so that they are each under a better supported part of the hull. Front cradle under the front mirrage drive hole and rear cradle under the rear seat where ther is the support of the seat drain scupper holes.
I have now purchased a second pair of cradles. One of these wil be mounted under the centre of rear mirrage drive hole for middle support. Mounting a third cradle needs to be done so that it is set down quite a bit from the front and rear because of the curve of the hull down in the middle.
The extra cradle I have made into a dolly cart to wheel the TI down to the beach where there is no access for vehicles and a trailer.
I figure this gives me the best of both worlds: I have a trailer to cart it to the boat ramp or launch from the beach, the trolley/dolly for paths to the beach and I have a side loader roof-rack for when I do a 4x4 trip to a remote rough track location where I can not take a trailer.