What is so special with the Top Mounts you talking about above ?
They are different (oh how wierd to explain in english since we both are swedish

)
On the left you have a CL/GL "standard" suspension. On the right you have the "GTI/Vr6" suspension:

The "Clima" vs Thermo" is kinda the same. Found a picture to explain why i keep coming back to that.
On the left you see a heather with non AC and on the right a heather with AC. It weighs approx 100kg. So you have 100kg extra and then the engine that weigh.

I however think your springs you found are up to it. And thats not the case am trying to tell you. Its the handling. It will be so bad consider all that weight. You wont be able to use your 16v as it was meant to be, cos you will loose friction to the ground.