Here’s the link for the Djet
https://volvo1800pictures.com/docume...lt_tracing.pdf
That cover plate left of the clock on the dash, is where a spindle mount radio would go. Those “radio delete plates” are like hens teeth, sought after by concours restorers, could be sold for a lot to help cover the cost of a modernized radio period correct looking radio.
I have one of those Classic Car radios, works quite well.