Cat chassis Is it a xl or xls

[Peakey]

I know they are basically the same chassis I have this and I now think it came from a xl is that correct and can anyone shed any light on it thanks

This one a bit rubbish but it's all I have at the min as they are at work

The idea was to basically build a xls from this how hard will it be

[Adam F]

Looks like someone has just made it as a school project as I'd did when I was a kid...