There are 2 places to mount the inner tie rods to the racks "center link". The lower holes are for small block. The upper holes are for big block.
Refer to Pg 2 of
http://www.totalcontrolproducts.com/download/instructions/7903-TIER-03.pdf
Did you install the spacers in between the center link and tie inner tie rod ball joints? Looking back through pics of my install on my 69, it looks like i would have your problem if the spacers were not there.
Do you have stock spindles?
Also make sure you not only have the correct inner/outer tie rods, but also that you have them mounted to the correct set of holes on the center link.
From TCPs FAQ page:
http://www.totalcontrolproducts.com/faq.html#TurningRadiuses
Rack & Pinion - Uneven left and right turning radiuses
A tighter turning radius in one direction indicates that the rack & pinion was not at its center of travel when the toe alignment was set.
Visual Cues:
* Uneven number of turns at steering wheel from center to full left and full right lock.
* Tie rod assemblies are different lengths.
o Can be verified with a tape measure or by counting the number of exposed threads on each side of the adjuster sleeve.
* With vehicle at ride height, check both left and right steering arms to steering stop clearance at full lock and compare.
Solution:
* Find center of travel of rack and pinion.
o With tie rods disconnected from center link, use steering wheel to find center.
o Count number of turns from lock to lock. Should be a touch over three turns.
o Turn to full lock, and then back one-half the number of total turns. Just over one and one-half turn.
* Adjust tie rod assemblies to even lengths then reattach to center link.
* Set toe, making equal adjustments to the left and right assemblies.
* Steering wheel may have to be centered once the alignment is complete.
* Tighten all jam and castle nuts.
* Insert and bend all cotter pins.