The Screamer is a project to build 2 famous overdrive pedals, the TS-9 and TS-808. Both versions are nearly identical, there are just 2 resistors different.
The new version 2 uses pcb mount pots and an adaptor board for the footswitch. This makes wiring and assembly much faster and safer!
The pcb dimensions: 55x55mm. It is professionally made, all holes drilled including silk screen.
Here the TS docs: Der Screamer docs
These projects are also available as complete kits!