1999 v70 XC/ Oil build up on everything. Best clean?

[Das_Rah]

We just bought a 99 XC with 181k and in pretty good shape except for the disgusting engine bay. Apparently someone had been driving it around with the wrong(and possibly none at all) oil dipstick for quite a while. There is major oil build up all the way back on the bottom of the car and coating the lower half of the engine. I need to clean it and do a tune up, but there is oil all over the electrical plugs so those need to be cleaned up and organized first.
I figured I would start with some CRC Electronic Cleaner and clean each plug individually *groan*, unless someone has some tips or tricks that might be better.

Any suggestions or methods on how to go about this?
I will post pics later, it's gross.
I appreciate any help you guys can offer

[JDS60R]

Buy Simple Green Pro HD ( Purple formula available at Home depot) And dilute to 25% simple green 75% water. I use a $10 1 gallon plant sprayer and spray the mixture over the engine compartment where dirty. let soak for 1 min and hit with pressure washer ( less water than garden hose) making sure to avoid the ABS computer ( I put a bag over it).

It will not hurt aluminum like normal simple green. If you don't know how to use , or don't have a pressure washer you can scrub it with a brush and then spray again or wipe down. This formulation will not hurt the metals if left to dry. It is less harmful than water alone.

If spraying paintwork dilute to 1 part Pro HD and 10 parts water.

[Ozark Lee]

I've had OK luck with some stuff called Purple Power (I think) from Advance Auto Parts if you don't have a Home Depot nearby.

...Lee