In post 332 in that thread, you should contact Geoff at Full-Race. He makes great manifolds and may be able to help you out.
I have used his stuff in the past.
206,500miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. CHECK your oil, these cars use it.
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