Holes in snorkel..........

One of the things I want to do something about on the Chevnissan I bought earlier this week is close-off 2 holes that one of the 2 previous owners has drilled in the bloody snorkel, in front of the A pillar. These holes are about 50mm diameter and were put there supposedly to allow more air to be provided to the hungry donk. There is also a small hole of about 1/4" right at the bottom of the Safari snorkel, presumably to allow water to escape when it rains....(gawd knows what they thought might happen if/when he went through a river!!!!!!!!).

Anyway, just seeking advice from any knowing person/s about how best to seal-up these holes. The small one can just be filled with some silastic I guess. But the 2 biggies will need a bit of thought, especially as they face forwards and are very prominent. I'm thinking that I should try to cut out some similar-type plastic discs, the same size as the holes and glue them (plastic weld?) in place.....but what adhesive would do the trick; Plastibond maybe?

Any advice (short of "buy a new snorkel) would be appreciated.

I guess I could try to source a snorkel (or at least that portion that i want to replace) from a wreckers etc. Does anybody know if the outside section of the snorkel finishes where it enters the hole in the guard? I'm guessing that it does and that immediately inside the guard there is another straight bit that goes down to the front of the inner guard?

Thanks in advance for all advice.

Roachie