hifi engine

Panasonic RA-6700

I need an owner manual and a service manual (pdf) for this old beast. I bought it at a thrift shop years ago and it sounds great. The cassette player doesn't work and one VU meter is not working. It's rare that I've owned something this long without opening it up, but it is now sitting on my bench. The cassette issue is likely a belt and I have lots of cassette decks so I'm really only concerned with the VU meter and what I might find inside (cobwebs, leaky caps etc..)
My searches online have found nothing in pdf files for this old critter. Has anyone else owned one of these.