Anti Roll Bar Technical Questions

[Sam]

Hi,
I'm rebuilding / replacing my 1979 GTV's rear end (DeDion., Transaxle, Hubs etc)  with parts from a 75 Twin Spark.

I want to replace the rubber bushes (backend and front end)  with Poly ones. While I'm at it, I'm also thinking of moving the sway bars from the Twinspark to the GTV.

The Twinspark bars seem 1 or 2 mil larger, but I don't know how much difference these will really make.

Has anyone done this? Is it worth doing?  should I go for an larger size ?

I'm hoping to hear from someone who has done this and can provide any information or guidance on bar sizes and difference it brings to the handling. (ie. 18mil vs 20mm,vs ?)

(Obviously it's cheaper to use the Twinspark bars as I have them for free.)

Thanks in advance
Sam