How do I find what winnebago I just bought?

We bought a 1998 Class C Winnebago motorhome with two slides: dining and bed areas. The certification label says it's a WF29B. The VIN only shows that it's built on a Ford chassis. I can't find anywhere on the web that allows me to input a serial number to discern the model. The previous owner thought it was a minnie winnie, but I can't find anywhere on the web that agrees a 2018 MW would have two slides. We need to order parts, but can't figure this out. Help!