Toyota Repair: Cylinder misfire and lean fuel, mass air flow sensor, mass air flow

Question
Please help! I have run out of ideas/solutions.

Toyota Tundra V8 2000.  120K miles.  K&N intake.  

Truck sat for 1 week. Very rough running and low idle.  Stalled twice.  Check engine light came on and would randomly flash.  OBD codes read: Random cylinder misfire, Cylinder #1 and #4 misfire, Lean fuel (Bank 1).

Cleaned air filter, throttle body, plug coils, and changed plugs.

Improved idle speed but still rough running.  OBD codes read same as before with Cylinder #8 now misfiring.  Sprayed MAF (mass air flow) sensor with carb cleaner and changed fuel filter.  Swapped coil of plug #1 with plug #3 to see if it was the coils.  Same running conditions but OBD codes are now only Cylinder #2 misfire and Lean Fuel mixture.

Can you please give some direction on what to try next.  Toyota dealership told me it was the MAF sensor that needed replacing.  I want to be sure before spending a lot of money of sensors.

THANK YOU IN ADVANCE!
I would appreciate

Answer
The MAF will not cause a misfire but it can cause idle problems but I don't think it's the problem anyway as I have seen very few of them cause problems on the V-8 engines, the system lean condition is caused by the engine misfire and that is the root cause of the problem, the misfire must be corrected first, the check engine light flashing is an indication that the misfire is severe enough to damage the catalityc converter if not fixed. It's possible that a coil pack or two are the cause, this is common, were any of them replaced already?