For those interested, I amended the "Mods" .json file with what I have shown below as example
{
"name": "1900s",
"description": "1900s",
"filter": "tag:1900s",
"icon": "1900s.png"
},
{
"name": "1910s",
"description": "1910s",
"filter": "tag:1910s",
"icon": "1910s.png"
it is found in folder \AppData\Local\AcTools Content Manager\Data (User)\Car Categories
I then put a tag on each car corresponding to each decade, tedious work the first time but when adding new cars it is fairly quick process which i do when making my previews.
Shown below is the Itala where I added "1900s" as a tag for that car
View attachment 1160960
If any help I have uploaded my JSON file and Fonts .png files I made up for each decade, extract then transfer these directly into the folder mentioned above and should work if you update your tags on each of your cars.
Quite exciting as I'm sure a lot more ideas could be made to filter and separate using this method. Can be a bit overwhelming to remember or browse all the great mods, even when I spend a lot of time reducing the content kept on system.