#include <bits/stdc++.h>
using namespace std;
int a[100000];
void solve() {
  int i, j, n;
  cin >> n;
  for (int i = 1; i <= n; i++) cin >> a[i];
  bool ok = 0;
  for (int i = 2; i <= n; i++)
    if (a[i] != a[i - 1]) ok = 1;
  if (!ok) {
    cout << "NO"
         << "\n";
    return;
  }
  map<int, int> M;
  int minc = 100000;
  for (int i = 1; i <= n; i++) {
    M[a[i]]++;
  }
  for (int i = 1; i <= n; i++) {
    if (M[a[i]] < minc) {
      minc = M[a[i]];
    }
  }
  int root = -1;
  int val = -1;
  for (int i = 1; i <= n; i++) {
    if (M[a[i]] == minc) {
      root = i;
      val = a[i];
      break;
    }
  }
  vector<pair<int, int>> edge;
  int last;
  vector<int> free;
  for (int i = 1; i <= n; i++) {
    if (a[i] != val) {
      edge.push_back({root, i});
      free.push_back(i);
    }
  }
  vector<int> same;
  for (int i = 1; i <= n; i++) {
    if (i != root && a[i] == val) {
      same.push_back(i);
    }
  }
  for (int i = 0; i < same.size(); i++) {
    edge.push_back({free[i], same[i]});
  }
  cout << "YES"
       << "\n";
  for (int i = 0; i < edge.size(); i++)
    cout << edge[i].first << " " << edge[i].second << "\n";
  return;
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  int t;
  cin >> t;
  while (t--) {
    solve();
  }
  return 0;
}
