Its so hard to stay outta stuff like this, but I know I should,....because I have to be missing something

But if the head is coming off anyway, why are we worried about cleaning it now. Wouldn't we wait till the head is off, then either spray it w/ carb cleaner, or if you want it bare alumunium, take it uptown and have a commercial "hot tank" it ? But here I am again, ...back to logical thinking,.....I should know better by now.

MB, Answers come fast and furious on here. But the Truth...well that's a different matter.  

Truth ?? Next time say so !
Ok, find a pot in the kitchen big enough to submerge the head in,...yeah, the crab pot will do it.
Dump a couple cups of your favorite laundry soap into it, fill it w/ water, stick it on the crab pot burner, or a burner on an electric range works best, and bring it to 180 degrees, and let it set 6-12 hrs, then hose it off.
DON'T use caustic soda in the pot... on aluminum ! It will start foaming, and your head will be a lb or 2 lighter in 8 hrs But caustic soda works great on any steel or cast iron.
Oh yeah, I used to have a rental hot tank business years ago. I had 2 types of tanks, 1 for aluminum (kinda like tide soap only different) and the other for steel (caustic soda)
Well, story was,... this one customer mistakenly hung 8 rods and pistons on a wire in his caustic soda tank overnite, removed nothing but the rods in the morning!!
Highly exaggerated for the story I know, but it did ruin the pistons :'(

Serenity, I have been put in my place. And I never saw it comin'.

stinger, oven cleaner is sodium hydroxide (lye). It can etch the aluminum and make it porous which, in turn, makes it harder to clean. Someone used it on my daughter's TRX 300. Ugly motor. Runs fine. And that's the Truth as far as I can tell.