Wheres the best place to make the connection for a decent reading?

• Tap EGR
• Tap one of the swirl flap blanks
• Tap any of the existing vac lines?
• Tap...somewhere else

For coolant temp reading, will tapping existing temp gauge work or will splitting signal here throw off the reading for something else (http://www.realoem.c...315#13621433076 - number 6) or am i just better off getting one of these universal jobbys for fresh feed...

http://www.ebay.com/...T-/381365055538

Ta in advance