I love the finished boots, you did a really good transformation on them.
I bought myself some black Chelsea boots for my suit and decided to dye them white with a TRG leather dye kit shade 101. I used the old blue masking tape route for protecting the soles and heels.
When I used the kits sponge applicator I was glad I put vinyl gloves on because that stuff dries like rubber on the tips.
I wish my elastic sides covered as nicely as yours did, mine had a rougher material, yours are awesome.
As the boots get more wear the black may show through from underneath...I put 6-8 layers of white boot polish over mine and the shins still sliced the dye layers off.
One of the guys who troops a lot locally told me he sprays his boots with Plasti-kote to give them some protection .
I carry a small bottle of white correction fluid in my armour bag for emergency touch ups if needed.