Have to be very quick as I'm at work

I have a leaking sunroof....it was the drainage hole that was blocked but after removing the roof, the screws tapped into the roof, holding the lifting mechanism in, also seem to be leaking, resulting in a much slower flow of water into the cabin. This was probably because I gave the sunroof a hard push or two before i figured out how to remove it

If i remove the screws and silicone seal them in, it shoudld make a water tight seal. However will doing so make it difficult/impossible to remove the screws at a later date?

I will be doing it tonight if i don't get a better suggestion.

Sunday I had about 5 cms on water in the drivers footwell lol, I could see the water pouring in..now its just a few drips, but with the winter weather, needs to be fixed ASAP.

I'm hoping the seal is ok itself...if not, thats £36 from fiat, and 2 days wait! DOH!

Cheers for any help or suggesstions,

Kristian