Service information (late 1979) for JR596W was published in...
Sams Photofact service manual Set-1824 Folder-3
it also covered these models/chassis...
ref:
https://www.samswebsite.com/en/photofac ... sid/1824_3It is difficult to find. Keep an eye on ebay.
Be very cautious of websites offering digital downloads, as many of these are scammers.
Sams website will have a copy for $22.00 - be aware that it will not be a high-resolution copy.
Greg.
Operating guide. View on-line or download as a pdf.
https://archive.org/details/OperatingGu ... soleStereo