Jeff - I just want to ask about the timing of the bluing steps. On the weld line how long did you wait before applying the additional strips on the side?
By the time you get to the other end you can wipe (in the direction of the stripe) with a paper towel to make sure its dry and pull the stripe tape
And then how long till you sanded for the blend?
Your using allot less liquid and not letting it "sit" so you get a light discoloration. Once you get it applied it should be ready to peal back the tape and feather the edges. The product recats (when applied with a rag or brush almost instantly and leaving it longer than a couple of seconds does not make it any darker.
Do you apply another layer of bluing over the center stripe as you do the sides?
Yes it is easier to just redo the tape spaced further out on both sides and cover all three (dark stripe, and both sides) at the same time and it eliminates the possibility of leaving a untreated gap at the edge of the dark stripe
I'm probably overthinking it but questions can be easier than re-dos.
Don't we all
Great things is this is likely the easiest redo that I know of
If you have a piece of oil free bare steel (like a small sheet or bar) practice there first if you want to get the hang of it