1999 Chevy Silverado 1500ls 4.8l v8

Okay iv had my 99 Silverado 3 years before
me my grandad owned it up until around a
year ago it ran fine one time it broke down
and the guy working on it at the time said it
was maf sensor and he cleaned it and said
to replace it asap, around 6 months later
fuel pump went out so we replace
pump/filter, (never replaced maf sensor)
when I cranked it up for the first time in
months after pump was installed it smoked
some but it was manageable that was 2
months ago now I can't crank the truck for a
second without big white clouds of smoke
pouring from the pipes the color of the
smoke and the smell is for sure raw gas it
idles around 600rpm if I crank it and let it
set in park I can unplug mad sensor and
rpm's go to 1000 and the idle isn't rough at
all but it seems to smoke more if I do that...
What do I do?!?