[Thinking=out loud]
Looking at controls.dat info, it looks like mame used to use dial input type, but looking at current mame source now uses paddle type. comments in the source includes, "// steering wheel, not exactly sure if DIAL works ok.", which hints the coder thought it should be dial. Hmm, there are quite a few unknown dipswitches; could this be another GTMR-like game that can (dip)switch between different wheel types? [/thinking]
Hardware confirmation needed.
(But unless those dipswitches are also confirmed as not changing input types, one report on the wheel type won't be enough to be totally sure.)
edit: clarification about current mame.