You don't need to vacuum fill those cooling systems. Remove both caps on the surge tank. Fill it up. Cap off the over flow drain tube by the top side cap. slowly fill and let coolant fill the other side of the reservoir. needs about a qt in the other side of the tank if that makes sense. Dealership tech. I've never vacuum filled a l5p.
Good series brother learn a lot from your videos. You need to try kroil penetrating oil. It will make your life way easier on them tough bolts . Wd40 haves nothing on it at all .
I never was able to get a hold of you on Instagram I had a question what turbo you would recommend compounding for a 1000 horsepower 5.9 I have all the supporting mods to make it including the injectors, currently I have an FIS s472/83/.90 made 722hp at 3800rpm spools nicely wondering what I should put over it?