On top of the Back to the Future car radio sit an aluminium heatsink and PCB 

They are the measurements of the heatsink 

The PCB fills the entire length of the radio and had 2 holes in the front 

The heatsink and PCB have multiple compentents attached:

1 Honeywell 3001U (with red wires)
2 2N3772 Tesla Transistors
2 black resistors (undefined)
1 smaller resistor (undefined

We recreated a movie accurate radio heatsink out of extruded aluminium :