The EA engine bay is hard to keep neat.. especially with the MPI manifold.
When I installed the EF manifold, I managed to run all the sensor wires under the manifold, which helped to neaten things up a bit. As for keeping the dirt off, most of the time it gets a clean every time the car does.
A problem area with the wiring neatness is along the drivers side strut going to the battery, I cant seem to think of how I can neaten that area up without some major work involving relocation of all relays.
I reckon a good starting point would be to give the black plastics a coat of paint if needed, and then give the rocker cover some attention.
Pics will help!
CAUTION: Slippery When BOOSTING!