I see no reason why it wouldn't work. Make sure you have the kit for the 68 collapsible column. You will have to shorten the lower shaft for the bearing and U joint shaft to fit just like the non tilt column. No modifications to the upper shaft or column so I see no reason why it wouldn't work.
See other threads on installing rack and pinion steering. There is lots of information. I installed the Unisteer power rack on my 68. I disabled the tilt-away because I didn't want to be bothered with it, but there isn't any reason why it can't be functional. The steering column mods are at the bottom end for connecting the universal. Having read about the TCI unit, my vote is still for the Unisteer that I installed. I think you will find it is cheaper even including the pump and hoses, than the TCI. I am running the Unisteer rack with my stock power steering pump.