I always read owners manuals and get shop manuals if I think I need one. The first Bridgeport I bought was used, I bought it in Cleveland and trucked it home in my pickup truck. Before I even assembled it in the shop I called Bridgeport Machine and got the books. Engineers compile all sorts of good things in books....even the cryptic owners manual that comes with the Rocket.
Some years ago I bought a really old (like 1940's era) South Bend 9" back geared benchtop lathe with a quick change gearbox. It came in a couple of boxes, covered with grease and grime. Thanks to the good graces of the South Bend Lathe Company in South Bend, Indania, I was provided with copies of proprietary prints as well as a vintage owners manual. I took me 3 years to completely rebuild the machine. I had to cut gears, scrape and true the bed, replace the plain bearings in the headstock and many more time consuming tasks. If it wasn't for the manual and the blue prints and specifications the company provided I couldn't have rebuilt the machine, a machine I use all the time. Sadly, a year or so ago, the South Bend Lathe Company went bankrupt, their assets bought by LeBlond who liquidated all that was left. That's made the machine very collectable and intrinsic parts very expensive. Sometime, go to flea-bay and type in 'South Bend Lathe'....you'll see what I'm talking about.
There I go, rambling again....................