If you can find an LFS
in your area that has actual O2
for shipping, you can bag up the fish and have the LFS
fill the bags with proper O2
and add a few drops of an ammonia binder like Amquel or similar. It will be much less mess and hassle in regards to loose water in buckets and the fish will be much easier to acclimate to the tank. This method will also cut down on stress and the high O2
content will help keep the ph
in a better range. The bags can then be packed in a styro box to help keep in the temp better.
The rest of the plan seems sound.