So for a first try at mud, I had a look at
https://www.youtube.com/watch?v=8MBfYwk42A8 and had a go with some dry mud splashes from Ammo. And, yeah, there are issues (still damp with thinner btw, if it looks strange).
I guess working around with airbrush pressure and control (aka git gud, though of course that's a goal for some distant future, ain't gonan help here) could help get the mud to spread finer, instead of large blotches, but I'm starting to wonder if the whole approach may not be deeply flawed for this case due to the wheels and so on being in the way. Front and ass don't seem qutie so bad. Working up some kind of density of mud splatters seems like it'll take an ungodly amount of passes here, and leave wheels and whatnot completely drowned.
I guess dabbing on a good amount of the wet earth effect in the lower regions may help, but, yeah. Being new to mud I'm not even sure I'm pointing in roughly the right direction here.
So is there hope here or should I just clean up as best I can and then go for a heavy dusting of Russian soil pigments for the dirtying up (and hiding some of the worst of this step)? Try to build up a higher density of splatters at elast in the mid region, so I cna transition itno the darker mud lower/around the wheel suspension? However I'll get that on, something stippling-like I guess, because aiming the blown-off-the-brush mud down there seems rather too optimistic.