You've been on a TrackMaster Season 4 spree, haven't you? Nothing wrong with it by any means. I love that season and the Skarloey Railway in general. The engines, coaches/trucks and locations from it are always fun and refreshing to model compared to the standard gauge ones.
On topic: I have a feeling his face is built (not moulded) into the radiator, meaning the piece could be made of two layers. Maybe you could find some way to push the pins out, unscrewing the black drive unit supports to leave more space beforehand. You may need to apply some force to get the pins out easily. Seeing as you're not going to retain the original cast of the face, you could try cutting or breaking the pins and see what would happen. If the radiator is a separate layer, there should be some indication (on the back) of how the face is mounted (screw/s, post/s or glue).
