I bought a set of TTI headers. I'll be pulling the 95 horse /6 and dropping in a fresh 360, on a couple of weeks. Thanks for the replies, I was wondering if I should take it off or leave it on.
As said drill 4 more 1/4" holes in the flat plate you have and reinstall with new gasket. a NAPA gold #1068 or equivalent Wix will work just fine with the TTis - don't install filter before installing headers.
FYI - to make installing the TTis a little easier -disconnect the idler arm at the frame will give you more freedom to move things. Tey are a tight fit but well worth it IMO. you may have to raise the passenger side of the engine to get clearance between the header and the drag link/idler arm pivot nut.I added a 3/16" U shaped shim under the motor mount so mine would clear.
Have fun.