Actually it's been two years since I ran it.
Pulled electronics and fogged it at the time but was rushed (away for two years) and didn't clear the fuel. Before this past winter I pulled the plugs and fogged pretty heavily and drained the fuel tank.
Trying to get it started now. I have changed the plugs, cleaned the final stage fuel filter, set up a temp remote fuel tank. I have tried priming the cylinders with some raw gas and it does fire but each time it seems to just burn the added fuel and never really runs more than a few seconds. It's pretty smokey which I expected from the heavy fogging but it will attempt to start a few times and then give up.
When I pull the plugs they are oily. Fuel system gummed up? No new fuel mixing with the oil? There was old gas in the internal lines and when I drained it to clean the filter it was quite yellow.
Any suggestions how to proceed? I do have a shop manual but I have only done some basics (and missed some of those I guess)
Don''t spray raw gas into the carbs. You will damage the cylinder walls without the lubrication. Mix some 50:1 gas:oil mix and spray that into the carbs if you must.
Regarding your start up problem. I suggest that you clean the carbs and rebuild the fuel pump. These are maintenance items anyway and appropriate to do when a motor has been sitting unused for as long as yours. After doing this and the motor still does not start, then I suggest that you do some systematic troubleshooting of the fuel system. The below link provides some guidance for testing for fuel starvation.