Two genes, same MCS - (Apr/13/2013 )

Sorry if this is a repeat topic, I have looked/searched.

I have a vector that I am trying to give dual resistance to depending on cell line I want to express in.

A coworker said I could just put the puromycin cassette into the MCS but I am just wondering if this will cause problems? Two genes in one multiple cloning site?
It's a C1 vector but if I put a stop codon after the first gene, will the second one still express?

The MCS is just a site with lots of unique restriction sites in it, it doesn't matter what else is there. So long as each gene has its individual promoter associated with it, then there shouldn't be a problem expressing.