If it is gonna be a Merc, then it's probably the SL65 BS from FH4 which was removed for absolutely no reason whatsoever except to pad out the updates. Would be much better to get the new A45S or GT BS...
If the 5 down does end up being the SL 65 BS, then the 9 across could be 86GRToyota, which I know is a really massive stretch, especially since 10 down would then start with a "y", but one can dream
Edit: I just remembered that there was a Yamaha Raptor 700 leaked in the texture files last year, and Yamaha 700 would fit the 10 down if it started with a "y" but who knows, would be an interesting addition