Vacuum line for Boost gauge

[krystalized_jdm]

I've never actually done or put one of these in myself. So based on what I've looked up and heard. I've come up with two options, before the throttle body which is better for boost spikes? (correct me if im wrong, internet is a bad place xD) and after, which shows vacuum and boost.

Which is better? Also, what line should I get into my line for my BG?

[DarkCaporaL]

Just T into the same line as the stock boost gauge line that comes out the plenum in the rear close to the firewall.