Hello all,
Basically you should run around with out the plugs in in normal conditions,
as stated above, there needs to be a release if any leaks develope around the clutch/drive shaft area seals.
If you go through the odd bit of water, more splash than river beds then you will probably get away without fitting plugs.
If you intend to go into deeper water for longer periods then plugs are advised.
Just take a look under the engine and bell housing,
you will see a 13mm threaded hole in the bottom of the timing case (front of engine) and the same on the bottom of the bell housing.
Some TDi's have only the bell housing holes, some have bell housing and timing cover holes, TD5's do not have any.
The plug is usually a square drive bolt head at 10mm, you will need a 10mm openended spanner as a socket or ring spanner will not fit the square drive.
You can pick them up at the shows or sort outs.
Cheers.......................