Front anti roll bar diameters

Does anyone have available the irrefutable diameters of the front anti roll bars please?
I gather that the softer comfort springs demanded an increase in diameter for the front anti roll bar but from what to what?
What I need to find out is what has been fitted to my car. It could be standard for year (2002/3)
If I measure the OD including the protective coating (probably a PU coating) I get 20mm.  

I believe the really thick one was 25mm. But what was the diameter of the bar fitted to the car as it left the factory with standard springs?
Can anyone help with that please?

Come on chaps someone must know the answer to this please!
 

I for one don't know.......have you checked the specifications section of the workshop manual? Maybe the enlightenment you seek is buried in there or check Rimmers catalog they may have the info listed with part numbers.

Yes, I have checked.
The potential confusion is that at least one respected source suggests that there was an increase in diameter for the softer suspension, and that at the end (85th) that the bar was thicker still. That same source suggests that there was a 2mm difference between one bar and the next.
It is fairly certain that the thickest was 25mm.
One dimension (recorded in the manual) is noted to be 20mm, but that doesn’t say whether that is the thinner or the thicker two.

I need to renew the struts or at least the springs to resolve the ride height that is way too low.
It is my belief that the PO fitted the comfort pack springs (or some with a similar rate but not necessarily the same free length or possibly same rate but shorter).
Clearly the PO changed the springs - that is obvious- what is not known is what was done to the anti roll bar.
A rough check over the PU coating suggests that diameter is 20mm. That suggests the actual bar might be marginally thinner than 20mm or the bar is a nominal 20mm.
Common sense suggests that if the original springs are re fitted then the first (smaller diameter) bar needs to be fitted otherwise it will be too stiff. Hence the need for clarity.

I think you are correct with your 25mm, obviously this is going to increase the torsional stiffness & tame any wayward roll.
I looked into changing my standard bar to the uprated offering but couldn’t find one which was wallet compatible.
I had a collection of rose jointed rod end, enough to assemble a full set, which gave me a range of adjustments from standard upwards. I adjusted them buy the same degree, enough to make it obvious there was more tension in the system & subsequently forgot about them.
As expected there was a little less body roll (or was it psychosomatic),
It was quite a long time ago.
I look in on them when I’m in their area & they are still well & quite shiny.
M

They can be as clean as they like. I’m still eager to know what the diameter is for the two thinner ones.
Ideally someone with known provenance for a 2002/2003 car to measure the diameter of their ARB.
Any chance please?

I have a 2002 Tf 135...std original car. I will measure it tomorrow. 
It looks like new so no pitting and should be accurate using callipers.