Here you have two places that will answer most of your questions about modeling.
http://www.scalewiki.com/
http://www.automotiveforums.com/vbul...d.php?t=215864
When I wire an engine I prefer to use copper wire in different sizes because it bends without kinks, holds the form and is also easy to paint.
Drill a corresponding hole, put a tiny drop of super glue on the wire and push it in place.
Bend, trim and glue the other end and it's ready for some paint.
Looks something like this.
For the plug boots I use some insulation from a very thin electric wire with the strands pulled out.
Here's my tutorial on braided hoses;
http://niclasproos.fotopic.net/c193019.html
Good luck!
Niclas