anyone want to throw out some advice?
I'm not sure if this is 'advice' since I haven't made this yet, but:
1- the day before brew day, take 100 grams out of the original 4lbs DME (or use an additional 100g, which is what I will do) add to 1 liter of water, boil for ~10 minutes, cool and put into a container to pitch the OYL into it. I would not do this in the carboy. Find a mason jar/water bottle/etc and cover the top with sanitized foil and let it do its thing.
2- after you have made your starter for the microbes (step 1) heat 6 gallons of water to 200, stir in 4lbs DME to pasteurize, cool, siphon the wort into the carboy (IMO siphoning is superior to pouring at this step to keep o2 out, which is crucial for now) and pitch the entire 1 liter starter containing the microbes into the carboy. Purge the carboy and install airlock for 24-72 hours or until it is at your desired acidity level.
3- once it is at the acidity level you want, siphon BACK to the kettle, boil for a while to kill the microbes. At this point you can how POUR the cooled wort into a cleaned and sanitized carboy.
KEEP IN MIND that any plastic (siphon, bung, airlock, paddle, etc) which came into contact with the wort prior to boil is now contaminated and should be designated as sour equipment!
4- pitch the package of nottingham into carboy and affix a NON-SOUR bung and airlock to carboy. Given the low OG of this recipe one package should be plenty of yeast. Proceed as normal from here.
If you wanted to pull some bugs out to save for the future, you have to pull 1-2 liters of the wort out before you boil it, put it into its own container (glass is better) and top it off with a new mixture of wort (100g DME:1liter water). This process is not diluting the bugs, it is simply making them reproduce and multiply. When you decide you want to use some of this new culture, you can decant some of liquid, swirl it all up and pout ~1/2 into the new batch, then add new wort in to continue building the culture. Hope this was some use to you. Cheers!