issue gettin my 99 blazer 4wd 2d started
 

title says it. i have a 99 blazer 4wd 2door, since its started getting cold in michigan ive had a hell of a time getting my truck started only in the morning. after it warms up, its good to go for the rest of the day, i was told the distributor cap an rotor, so i changed that, worked for a momment, ive changed the battery, the coil & ign module, plugs an wires an the cap an rotor. im starting to get irritated, im not a master mechanic but i do alottttt of small end jobs. an can usually figure the problem out. but back to the issue. when i turn the key over, it'll sound nice an strong, it'll crank an crank an crank, some mornings after about 8-10 cranks of turning the key over, it'll start, but not now...; any ideas?

ooh also ive tried starting fluid an it didnt do anything. thinking its a spark issue. but im not sure. but ive also have changed just about everything that would interfer with the spark. havent i?