First two steps of the conversion: the two shotguns barrels become volleygun barrels. I give to Tallarn Sergeant a laspistol and I upgrade his sabre to a power sword:
A step back:
Before I have made a twin 2WW Bren indeed, a better choice for the officer with berret. But I changed idea and his head too, because I need it, and I carved another one from a Space Marine Scuot's nape.
Other pics of the renovated miniatures (referring to Tallarns, old colour schemes are reduced to two now...):