Shell Programming and Scripting

Let's take a set of the simplified sample files to ease debugging/understanding.
kyl1.txt

Code:

1 2 3 4 5 6
1 2 3 4 5 6

kyl2.txt:

Code:

7 8 9 10
7 8 9 10

Task: substitute columns 2 through 5 in file kyl1.txt with columns 2 through 3 from file kyl2.txt.
I think this sufficiently mimics your original objective. Correct?
nawk -f kyl.awk f1s=2 f1e=5 f2s=2 f2e=3 kyl2.txt kyl1.txt
kyl.awk:

Code:

FNR==NR {
   for(i=f2s;i<=f2e;i++)
      f2[FNR]=(f2[FNR])?f2[FNR] OFS $i:$i
   next
}
{
  $f1s=f2[FNR]

  for(i=f1s+1;i<=f1e;i++){
     $i=""
  }
  sub(OFS OFS , OFS)
  $1=$1
  print
}

output:

Code:

1 8 9 6
1 8 9 6

Is that what you're after?
If so, substitute the 'f1s=2 f1e=5 f2s=2 f2e=3' with the start/end column values for respective files.