I just found a site that contains manuals for a wide variety of equipment, and I see some tractor and other heavy equipment manuals on the site. The site will allow you to download manuals for free as long as you upload some of your manuals. If you do not have manuals to download, then you have to pay for the download. You are issued credits to your account for the manuals you upload, so basically, upload any type of manual and then you can download any other manual for free. There does not appear to be a file size restriction. All manuals must be in PDF format.
The website does not appear to have any malware or contain any advertisements. So, just sign up.
This site has a vast amount of service, parts, operators manuals for everything including electronics, machinery, consumer goods, power tools, tractors, generators, computers, furnaces, etc.
Be patient, the search engine appears to be very slow, but it will eventually give you an A to Z list.
https://manualmachine.com