Can I transfer my customizations from LL3.8 to LL5.2

[mezzmer]

I have been using LL3.8 on a VM for a couple of years, but with EOL coming up, I want to move to LL5.2.

How can I  transfer the following customisation/configuration:

1. Initial boot screen (Gradient Gold with a LL Feather) ... It seems to have disappeared in LL4/5.
2. Greeter window background colour
3. Desktop background set to solid colour
4. Task bar, Change colour and panel setup

Is it possible to just copy some configuration files/directories?  If so, how do I find out what I need to copy?