I have with file test.txt with contents as below 1:2:3 123:5 34589:5:0 34567:8:7 781:9:09

Can you please help to get output below from file as below 34589 5:0 34567 8:7 781 9:09

Explanation : below line contains highest number column i,g. 3 and removed :

34589 5:0 34567 8:7 781 9:09