You can't learn about how to build an engine correctly over a few weeks on a forum. I'm not being harsh, I'm being realistic. He doesn't know what he's doing and it will end up costing him more money. I've offered him help, so I'm not being harsh at all.
For the record my name isn't Paddy, nor do you have to use VW sealant. High temp RTV silicon is what he needs.
If you don't know what you are talking about then don't second guess or miss inform people, because that's how mistakes happen.