The 4% rule is unamagical thing if you get a really bad market and lose 50% in a year and next year you only have half as much to spend as you had it before so I don't think that that's a Hold it a call other things come in in life where health or the markets can blow apart your plans so I would...
I've used them for metal screws, not in wood. Can you share a picture of what you are working with? You might get better suggestions on how to approach the problem.
What kind of trust?
I would document the intention so it is clear. writing multiple checks could do the decimation.
I would write 2 checks to make it clear to everyone years from now.