Like has been suggested...take a hand file, use some tape, and a vacuum 'trunk monkey' and artfully remove any down-stream interference and it'll pick the combo up for certain. Make you efforts/expense worthwhile. If it makes you feel any better you should know at Roush we'd occasionally tickle NASCAR intake manifolds ON THE DYNO to help fuel distribution. And he'd use no vacuum but blast it with shop air for clean-up. If you knew the man, you'd know he'd sell his soul for a good running engine, at that time anyway.