Help me build a Burton Union

I want to ferment in a pseudo burton union. I want to harvest yeast from the union - why because I think it will be cool. I have a bucket fermenters. I will use a secondary vessel with plastic bulk heads to attach to regular siphon hoses - I think I can make that easy. Problem is I can't figure out how to make the union through the bucket lid. Anyone got any ideas?

It's done with a carboy here, but I'm sure if you have a tight seal on your bucket fermenter and a longer tube going into the fermenter down to the level of the krausen you should be able to pull it off just like this.

Top cropping yeast from a carboy. - ALEiens Homebrew Club

2 grommeted holes with blowoff tubes in each. The one to the bottom of the union, where the spillover goes back to the bucket is inserted below the top of the wort level, The other hovers above the wort like a normal blowoff tube and when the fermentation explodes it will push out through that hose into the top of your collection vessel. And you don't want too big of a fermenter because the blowoff is the whole point of doing this.

BYO had an article on how to build it.

-OCD