I got this project, non running/80% complete, for $420 and a bottle of Gentleman Jack.  I cleaned the carbs and got it running, but it smoked like a big dog so I pulled the engine.  

And already got a Babe to pose with it.

Before I remembered the side covers.
Couple of interesting things:
I scrapped the 78F motor for a 73 K motor, courtesy of Ricky Racer
Installed the Cycle X offset sprocket to line up the chain
Did a 530 chain conversion
1975 CB750F Carbs (75 spare motor waiting for the "love")
Carb rubbers from Ebay-that guy in Germany making knock-offs (kenosha_kid)
PowerArc Ignition, from Cycle X
Thats a MAC header that I lost the can for, and made a baffle with rolled up perforated metal and a custom endcap.
The seat is a 75-76F pan that I chopped up.  I cut off the part that flips up after the brace, narrowed the whole seat,  then welded a tunnel onto the end.  I cut the end of the tunnel and welded it up to resemble an older stock seat, but with a nice bump. (forgot to take pics during,  

)
This incarnation was just to get it running again.  I have a cb550 rear fender I may be re-installing.  I have a GL1000 front end/wheel and 75F rear wheel I am planning to install.  I also have a 75F motor I will be going through.  I have a Gordon Frame kit on order - with Hednut, and I will be painting everything as well.  I am also going to try installing all the engine bolts, swingarm bolt and pegs from the 75F to get rid of the aluminum rearsets from the 78F.  I may install some F4i rearsets I have laying around, we'll see.
Updates to come soon.