This is my 1970 CB750 with a K3 motor or so it seems by the serial numbers. I paid $150 for it, trailered it home and have started the full disassembly. I cut off the rear end a put in a hoop. I'm swapping the rear swingarm from a 1975f0 swing arm on to the K0. It will consist of a full swap of parts. Swingarm, Brakes and 18 inch rim. Here are some pictures of the bike when I got it home and now just about fully disassembled.
Excuse the mess, when your married with three kids I can't keep anything clean.
The bottom picture is how it looked when I picked it up. I guess they uploaded in reverse. The motor is free and on my harbour freight compression tester I'm right around 95PSI with out the carbs or exhaust attached. I've fully cleaned the carb and I'm in the process of reassembling those now.