74 Duster, resto mod 6.4 front end rebuild questions

HemiDenny said
simple mod for more space and ease install / removal.

HDK replaces the lower portion of the 2-piece shaft with a piece of 1" DD that is held solidly in place by two set screws and a new sturdy bearing. No longer a need to loosen the column once in place

lower section of 3/4" DD slips into the 1" DD and cut with approx 2-2-1/2" into the 1"'DD. The 3/4'' DD shaft will slide easily in / out but is held securely into the 1"DD

use a Borgeson vibration dampener / u-joint to connect to the 3/4" DD shaft to the OEM shaft spline.

the shaft size is now 3/4" solid vs the OEM hollow 1-1/8 od and makes install or taking off or completely out a breeze.

I couldn't get the photos to load in messages, so the bourgeon coupler is just ever so slightly smaller than the coupler that fits the PST steering box. Looks to be just over 1.5mm difference not sure what that is in inches lol. Do you think i have the wrong coupler or a machining issue?

Edit just looked a 11/16th is 17.5mm and 19mm is 3/4 so that would make sense to why. (I think the standard manual mopars are 3/4 as well) I have contacted PST to see if they can confirm the spline size