i have just bought a boat and that person had installed gil marine wet offshore exhaust system on it. The risers he had installed are too high and exit through the hull too far up on the stern resulting in a poor seal and half of the bolt flange needing to be cut off since it is partially on the angle of the rub rail.
What i want to do is get rid of the Gil high risers and get a set of shorter risers to make the exhaust exit a little lower on the stern. I need your help in telling me the best way to fill in or patch the old exhaust holes so i can make new holes for the lower exhaust. I am attaching a picture so you can get an idea what it looks like. Your help is greatly appreciated.

By the way, anyone want to trade your lower risers for mine?

http://i125.photobucket.com/albums/...at/100_4520.jpg

http://i125.photobucket.com/albums/...at/100_4521.jpg

http://i125.photobucket.com/albums/...at/100_4524.jpg

Pics dont work,,,but i help ya if needet.

you may not have to get rid of the risers. There are wedge plates avaliable that go inbetween the manifold and riser that angle them down more.

I'll dig out some pics of the best way to fill/relocate the old holes.