OK, your computer still thinks you are using 19# injectors so it is asking for x amount of fuel for any given injector pulsewidth but youu are actually getting (24/19)*x amount of fuel. Add to that a little extra because your PF is set higher than stock at 40. I'd start of by setting the FP to 39 with the vacuum line off and see if that helps any. You might want to relocate the O2's closer to the heads so they are getting readings that are closer to the firing event to improve the accuracy of the readings. When I had long tubes, my O2's were in the #7 and #3 primaries. That limits you to what's going on in those two cylinders but they are usually the ones that go lean at WOT.
The 93 cobra had 24# injectors but the stock MAF for 19# but the computer was set up to handle the difference.
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YO! Barry! You LOST!