Can my tourist visa be converted to a non-imm B at suan plu immigration when my government university gets me my work permit?

In most cases immgration won't do a change of visa status for a B visa. Since it is a goverment university they might do it though. It would require contacting immigration to see if they will do it in this case

The work permit will not be issued until you have a B visa. With the WP 3 work permit application receipt and other required documents you can either get a change of visa status or a B visa at a nearby consulate.