2.0l 16v ABF on twin webers.........?

Hi guys

currently in the process of transplanting a 2.0l 16v ABF into my s1 gti resto project

My original plan was to just do a simple engine rebuild and then transplant over

but…….. I have seen a few twin weber conversions on the 2.0l 16v ABF

which obviously excites me massively

but here is the problem, what webers do I use in conjunction with my engine

is there a specific size that works best with this engine

im led to believe from a small bit of research I did that running to big of a carb like a 45 with give me a lumpy tick over

where as running a 40 would be a lot better, I also know it has a lot to do with the internals also

but that's about where my poor amount of knowledge on weber carbs ends I'm afraid

can anybody help me out with any knowledge they may know….

kind regards