You have linked a source code repository of programs and units written for TP7.
The sources of TP6 have leaked a few years ago. Search for exmortis on HN.
That "sources of TP6" you are referring to is not a leak but also a fantastic reverse-engineering job done probably 1993/94 and appeared 20 years ago on the web...
In this context, it's a really impressive work! Can you tell us more?