I'm going through all this atm. Been checking a few front ends I have & I can confirm the dimensions from top of plate to UCA bolt center; LH = 50mm, LX (pre RTS) = 50mm, LX- RTS = 65mm, UC = 35mm.
I have 3x LH, 1x early LX, 1x LX - RTS & 1x UC front ends to measure from so I agree with the above except for ohhgeee's 57mm for LH.
I have enough parts to make the ultimate A9X RTS front end but what I do have in my car atm is a bit odd & seems to work well for street/circuit except for the heavy steering.
I have a UC K frame with LH/LX UCA mounted 35mm from top plate. Torana stubs & LX steering arms. Steering rack is LH x 18-1 ratio. The car is lowered & on heavier springs & has a nice squat.
Wheels are 14x8 fronts & 14x10 rear. The front negative camber is noticeable when looking at the car & I can't find my wheel alignment sheet atm but what I can tell you is that I have no signs of uneven wear on my Yokohama 245/14/50 352. I reckon I've done about 10,000 klm so far. What it could do with is a UC or Harrop steering arm upgrade to level out & bring forward the tie rods a little more but other than that, It seems all is ok. You may see how the car sits in my garage photos.
Has any one seen this front end combination before? My whole aim is to do a better brake upgrade with the best of the RTS improvements but wondering if it's all worth it in the end.