Will,
Sorry, didn't realize from your first post you already had the 3V heads on an engine.
Kelly has good advice, believe me, I went through similar when I picked up a set of C302B heads and wanted to use my 48IDA manifold on them. I suggest you take Kelly's dimensions and draw out the two port sizes over each other, then it will be visually evident how much work you are in for. Also the Quella IR runner would need sufficient material up top to be able to port out the .36" to raise the intake port to match the CHI head port.
I can't believe Dennis wouldn't also sell an IR runner for aluminum heads, if so maybe he would be willing to sell or exchange your existing base IR runner for a high port version. That would at least get you a closer starting point. Again if the runners are independent (i.e. one per cyclinder head with a valley plate), then there may be more options to 'shift' the runner up and fab a new valley cover.
Good luck
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