Off topic:Reformat a table with awk

Question

[viv3kanand]

Hi, I have this table,

ID ref1 ref2
a   1   3
b   3   1
c   5   1
d   2   4

Tab seperated and there are n number of IDs (a,b,c,..) and references (ref1,ref2,... and so on). I want to replace the numbers with its corresponding ID if greater than 2, so the desired output will be like,

ref1 ref2
b     a
c     d

I have manged to do for single columns with awk

awk -F "\t" '{if($2>2) print $1}' filename

and

awk 'BEGIN{OFS=FS="\t"}$2>2{$2=$1}{print}' filename

But I can't use them for larger files.

Any help is much appreciated, Thank you.

Vivek