Vdo gauges a little help

Finally got the the vdo gauges one for volts and one for oil pressure. The one for oil temp was already there connected and working. But there were just two empty holes for the pressure and volts. Got the oil pressure sender as well. I would imagine the volts is just a case of wiring it up. What do i do about the oil pressure switch? My friend said I would need this? http://cgi.ebay.co.uk/VW-AUDI-OIL-PRESSURE-GAUGE-REMOTE-T-PIECE-KIT-3xM10-1-/350331973191?cmd=ViewItem&pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item519169ae47. It's a mk2 1.8 kr engine. Where does the oil pressure switch go? Tried following the sticky thread but i think a simple run through would help me with my non technical mind. Thanks in advance

You don't a pressure switch that's already fitted to the clocks [oil light] you just want an oil sender connected on the oil filter head .

Unless you have no working oil light ? Then you could fit the above Ebay item .

With work and life commitments i can be a little slow to get round to things. Any way on top of the filter head is the temp oil sender nearer the front of the car Further to the back the oil filter head is the oil pressure switch. The double pole Audi switch was too big to be screwed in as a direct replacement for the original Oil pressure switch( not the thread, just the senser) So i've switched the oil temp and pressure around on the oil filter head. Is this going to make any difference. I'm assuming the T piece was only if you wanted mfa to work as well as vdo gauges(Car doesn't have mfa) I've got time on sat to mess around making electrical connections. Just wanted to make sure I wasn't wasting my time as the temp switch and pressure switch had to be in the original positions. Some my questions may seem a bit simple to you experienced folk, but I'm just starting to get my hands dirty. Enjoying the experience so far.