I have a dab radio that is begging to be an amp can it be converted
Should be possible... The whole idea of turning a radio into an amp involves injecting your guitar signal into the circuitry between the radio receiver portion of the circuit and the audio amplifier part of the circuit. The trick is finding that "sweet spot"!
Yeah you can do that but as Jim noted you can inject it (probably) into the last stages of the amp circuits - this would require cutting traces to not have signal from the radios sound circuits. On the other hand it might be easier to keep the cool radio but replace the internals with a LM386 circuit -- circuits like RUBY or GEM or Noisy Cricket could work. Good luck on the project
I have started playing around with old radios and think I can get an old tube radio to be an amp. Your DAB radio may be a good candidate for this as well, question, does it have an "Aux" socket on the back? That would be problem solved really easy but I think it's an old radio doesn't have that, Let me know the make and model and I will try and see if we can adapt the circuit once I have found a drawing of the circuit.