I need help on how and where to do a vacuum check. I'm wanting to get a good look at the health of my motor before i go turbo. I'm thinking the vacuum gets drawn from behind the TB right. Are there any other places to draw a good idle vacuum?

plug in vacuum gauge here right?

 

UPDATE

Yesterday I did a vacuum check and got a reading of 17 at 850 rpm with an elevation of 776 ft above sea level. I drew the vac from behind the TB as describe above.

Any thoughts and opinions on the health of my motor with these readings? This weekend I'm going to do a compression test using a manual gauge. I will shoot a video and post it on youtube with a link and see if I can get any thoughts on my results.