I'm a smoker too....
My 82 K20 with a 6.2 smokes pretty good upon a cold start--it fills my shop up with smoke fast,I try to drive it out as soon as it starts,so I wont be breathing diesel soot and fumes all day long--it gets annoying,but thats the price of having a diesel I guess--I'd leave it outside,but it starts better when stored indoors,and brushing off a foot of snow to jump start it sucks after a storm..
Your truck probably would improve a lot if you put new glowplugs in it,and add some Howes diesel fuel treatment to the fuel--not having glowplugs working in the cold weather is the main reason for the smoke,the fuel piles up un the cylinder unburned,and when it finally does fire up,the excess burns off in a big white cloud--and if you have been using starting fluid,you might have already damaged a piston or rings--its liquid death for a 6.2--I use it only in dire emergencies....
My friend's ramp truck just blew a piston skirt a few weeks ago (another 6.2) and he had to put a school bus motor with 90,000 miles on it in his truck to keep it going--he learned the guy who borrowed it last hard time starting it,and used ether on it,without disabling the glow plugs--he got it started,and drove it 15 miles,clattering like hell--we thought the crank broke at first,till the got the oil pan off after pulling the motor...and found a piston skirt in the bottom of the pan..
It could be like tRusty said,the injector pump or injectors could be dumping too much fuel in,or poor compression(but I doubt poor compression,because you can start it without glow plugs) and other things like old fuel and air leaks in the fuel lines can cause bubbles and smoking--I'd try the glowplugs and fuel treatment first--but remember,even a PERFECT running diesel will belch SOME white smoke after a cold start,sometimes for several minites,till it warms up...
