Start LR6, Press CTRL+O, Select you current LR5 catalog.
No importing involved!!
LR6 will make a copy of the LR5 catalog and upgrade the 'copy' to work with LR6. Your library remains as it was.
(Do not try to re-open the LR5 original catalog a second time. )
You shouldn't have imported images again because the adjustments are not stored as part of the image file. They are stored in the catalog. You should open your Lightroom 5 catalog using Lightroom 6. When you do that you will be prompted to create a new catalog. You should accept that option. Lightroom will convert the catalog to the upgraded version. It will include all of your images and all of the work that you have done. Then you can get rid of the other catalog that you have created using Lightroom 6.
Very helpful, indeed.
Fixed it now.
Thanks for the input.
I have it sorted now.