The difficulty in installing the carrier; are the dowel pins. I am going to remove them, setting the carrier on the gasket and forcing it down (with C-clamps) to compress the pan seal. Then, installing the screws and finally re-inserting the dowel pins. This way the carrier can travel down against the back face of the block, and the pan seal compressed evenly.
Will post pictures. Got a dowel extractor tool as well as new dowels just in case.