Plenum Spacers --Anyone Done This???

[Nez]

I have read here at TRS about the Upper Intake [Plenum] Spacers.

Have any of you done this? and
What is the Max thickness of these spacers?

It looks as if I can add 1.250" or more.

Thank you all! Nez

1990 2.9

http://www.therangerstation.com/tech_library/PlenumSpacers.html