what engine should I do

[jsand6769]

So I have a 72k5 4x4, It is my DD now. I am going to tear it apart, make it nice and return it back to daily driver status( this is my choice instead of getting a new truck) so Which of the 3 engine trans combos do you all like

GMPP ZZ383 with edelbrock efi and a 700r4 (the easiest install)

96 to 98 gm 350 vortech engine and trans up grade (moderate install)

or Gm LS 6.0 and trans assy (most difficult)

I will have a 25k budgett for the whole blazer.

I am getting 8 mpg right now so I am figuring at least 15 with any of the combos listed, what do you think