Not seen a parts list/diagram, but pretty much a B5 on a B4 style tub chassis plate ... most B5 components will fit, except need B4 style servo mounts (through chassis) ... the plastic is different from both 4 and 5 series, and the hubs/steering blocks/etc will have less adjustability (no inserts) than 5 series, more like 4 series ... in essence many of same components shared with ProSC10/DR10/etc. likely ...