will a b6 xenon ballast fit a b5 xenon hedlight:?

I just replaced mine...
 

with a used unit off ebay. It wasn't an exact replacement because the unit we have in our B5 is considered a 4G unit the newer units made also by Valeo I believe are LAD5GL which can be found in abundance off ebay for around $90 bucks or so. The newer units bolt exactly in the same space with no mods. You must make sure though that the unit you get comes with a wiring harness which you can splice in very easily and a D2S adaptor. I hope this helps.

Really?!? Details please? Do you think it's possible to use an A6 ballast? I have 2 lying around