You can get new high speed ring and worm, but I believe he is getting 1600 a set. Ford had 7 to 1 and 5 to 1. The low speed is common and the high speed isn't as common and good ones bring a decent price. With our low speed set up and warford we can cruise at 25. A friend has the high speed with warford and he cruises at 30 to 35, but is constantly shifting when he gets in the hills, were as we just keep moving in overdrive. You'll have to tear the entire rear end apart and pull the worm of the driveshaft.