Its been suggested that when I fit a Gtech 1 chip I also fit a manual boost controller. I had a look at whats available some have 2 ports some 3. The original PRV has 3 but I understand people fit ones with 2. Whats the difference

And a boost gauge! (unless you have one). Don't know the reason but my old pvr had two ports and my boost controller only has two ports.. Think you only need the pipes what come out of the turbo.

A two port is a spring and ball type this opens at the desired boost.
The three type is a bleed valve this lets some air escape until the source boost >= waste gate required pressure (0.8 on standard car) + air lost through bleed.
EDIT: I should add that air is still bled off and when you are normal pulling vacuum it will pull unfiltered air in

You can also get an uprated solenoid that will do the job the old fiat one should do.

Make sure you check the fuelling too though and Don't be tempted to turn it up a bit further.

And a dyno run!

and a compression test!