Ok! Well, the help here has worked like a charm so far! Got the new carb on after 15 year old son perfected his ability to drop nuts into tight spaces on the fabulous Nissan 720 truck's engine compartment. Fuel line went ok, but the pipe is so close to the carb's fuel inlet that I now havea pretty curlique fuel line, but it works! There was only one vac advance line, which went right onto the port. Capped and plugged everything in sight, except the two steel pipes leading from the (old) air cleaner to the exhaust manifold. I did all of this without the manual or the carb instructions, which I inadvertently left at the office. Throttle linkage was a breeze, except I had to widen the notch a litle to get the flat on the linkage housing to go in there. I did not hook up the electric choke. Couple of pumps on the accelterator, and she fired right up! It runs fast, but I have not (a) hooked up the choke; (B) adjusted anything on the carb itself-it's straight out of the box. As I suspected, steel pipes leading to exhaust manifold also lead FROM the exhaust manifold, and created essentially jets of exhaust. I bridged these with a piece of heater hose with hose clamps, and it still ran fine. However, it has not been under load, nor at hi rpm, so I'm not sure if the exhaust pressure will shoot the bridge thru the hood and windshield or not. Per the above, I need to get the weber working right before worrying about this, which will be tonight's project.
Per the carb instructions, I need to add the return spring, though it's working as is. I was wondering what that piece was in the bag. I also need to add the float bown vent hose to the float bowl vent fitting, but I dont' see any hose that might be it, so I just capped it. I think it was capped on the old carb, but never found anything about a float bowl vent hose or anything like it. The carb instructions also say to hook up the idle cut off solenoid, which I just figured out, so I'll get that done, too.
I'll get some pics of the truck and the new setup tonight!