Don't bother to re-narrow the IH's, use them as is. Not ideal, but you will still be better off than stock. Then just go back and port the heads later.
H
During one of our FBI Pizza nights Marc H. asked if I had port matched the heads when I did the P&P. I told him I had and he mentioned that it was worth about 5 rwhp by doing so.
07-25-2009
Re: Porting Brain Trust, Help!
Don't bother to re-narrow the IH's, use them as is. Not ideal, but you will still be better off than stock. Then just go back and port the heads later. 
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