recommendation on good degreaser for engine, chassis, etc?

[Scruggs Family]

I, too, use Simple Green for an array of cleaning jobs around the cars...
good stuff.  But twice a year under the hood I use Amsoil's Power Foam.
Spray it on a warm engine, let it foam up and sit for a few minutes and
spray it off with the hose.  Then I use compressed air to blow collected
water off the compartment and engine.  At that point all the grit and grease
is completely gone.  I find that spraying the rubber hoses with a foaming
tire cleaner will leave them with a nice clean shine.  I spray all the nuts,
bolts, aluminum pieces and metal fittings with WD-40 which kills that white
corrosion that forms on aluminum and dispatches any residual water.  Finally
I spray the engine and compartment with Cam2 Engine Detailer.  Some may not
care the gloss that these resins leave but I find it pleasing to look at.
It is permitted to wipe down the excess for a 'less gloss more matt' finish.
I've found that the exterior plastics... headlight covers, tail lights and
such... will benefit from a spray called Plexus that can be found at marine
supply houses or online. YMMV. 

Regards,
Gross Scruggs
Annapolis MD