hi everyone.. my bulkhead is currently away been galvanised and should be back in a few days.. im just wondering what i will need when replacing it.. i havent removed the old one yet and ive never done one before so im not sure what will need replacing.. obviously i will need new vent seals but what else will i need.. i would appreciate any info anyone has,, as i dont want to be ordering parts every few days when i realise i need x y or z