Keeping floor screws standard BSF

[niftyrodman]

If you need to alter your floor, gearbox cover and want to install nut inserts like rivets with the special tool, the nuts closest to size generally come in metric. So, when the inserts are fitted, try a drill that just seems to start into the thread but no farther, then run that bit through the nut and the 1/4 BSF tap will fairly easily change the thread so all the screws in the floor are standard. If you dont run that wee bit of thread out first the tap will seize in the nut and spin the insert.