well yesterday i took my stock motor out and i just wanted to make sure that everything under the hood can get hit with water. i want to clean up the bay, can i leave everything where it is or should i really take some stuff off? i am thinking for the purpose of cleaning behind things i want to take some stuff off. also, the black insulation piece on the firewall can go right? or is it really there for a reason?
also, there is some surface rust under where the battery was, after i sand it down whats the best product to spray it down with? thanks guys. oh heres my bay now..

 

i just wanted to mention i am the master speller...

 

for rust try naval jelly

 

Yes the black insulation can go.

 

sand or sand blast the entire rust effected area, if you don't remove all of the rust it's just going to repeat itself in the future and thats NEAR future. rust usually comes back faster the 2nd time around. Use good automotive primers, I prefer House of Kolor brand. For final paint also use good automotive paint, rattle can just doesn't cut it when it comes to the elements, heat, oil/chemicals and water, etc. Do it right the first time, it will last longer and you will be happier with the final product.

BTW. I love my heat shield, you should be able to pull it off easily with the motor out like that. I love the OEM look under the hood

 

I would cover the master cyclinder, fuse box, and any relays with plastic bags. I think thats all that I can see from your pic.

 

also tin foil works good for covering items in tight spots for paint