Quick update, got the Spoon Sports rigid collars fitted on Wednesday evening. Picture #2 shows how much slop there is in the standard bolt holes. Pic #3 shows how the tapered shims centralise the bolts perfectly aligning the front subframe with the chassis.
There are 8 shims in the kit. It's just about do-able on axle stands (if you don't mind wriggling about on your back), only took me around 2 hours. Probably doable in less at a proper shop with a 4 post lift.
Next hoping to get some camber plates on followed by an Alignment before I can feedback with driving impressions.