Exhaust Manifold, To get a new one... OR not to? hmmmmmmmmm

So I'm in rusty ol' Canada and am getting a frame recall soon (salt ate right through the frame in the crease of the cab mount and frame) And am considering getting a new manifold since they are leaking a bit at the gasket, the truck has 200 000 km and the truck is literally coming apart for the recall SIGNIFICANTLY reducing labour time coming out of my pocket.

My question for anyone with experience removing a salt corroded manifold with around 200,000 km is:

how hard do these usually come out in terms of bolts breaking and having to tap them out?

Considering that the manifold is thick cast steel should I just replace the gasket and delete the cats when they go bad? (In my neck of the woods we have no emissions testing)

What are opinions on some of these options for new manifold/cat combos?

http://www.ebay.ca/itm/Catalytic-Co...2006|Model:Tacoma&hash=item19f0a9192b&vxp=mtr

or the dormans from rock auto?

 

Not sure if you can do this on the newer vehicles but I used to just punch the guts out with a pipe, start them up and blow out the chunks. Repeat as required.

 

I wonder how DTLTs would handle the conditions up there.

 

Spraying the nuts and bolts down with a 50/50 mix of Automatic Transmission fluid and acetone (nail polish remover basically) a few times ahead of removal will go a long way towards helping with any rusty/seized bolts. Even still, there is the possibility of snapping off a stud on the head. If you do that it is probably going to be a drill and tap to get a new one in there and it is a pain to get to the heads with them in the truck. It is not too difficult of a job, just be patient an don't be afraid to soak those bolts with the atf/acetone (or PB Blaster or other penetrating oil of your choice - it's just that the atf/acetone mix will work better). Headers might hold up better if they have a ceramic coating or are stainless. You'll still get rust, just probably not as much and not as fast.

 

I have a manifold leak on mine on the driver's side. Not terrible but annoying. The dealer did head gaskets on mine at around 123k miles and it sure looks like they put all new studs in the heads when they did it. Not sure if that's just procedure of if they all broke. I've done manifold gaskets on old crusty 22re's numerous times and I always seemed to break at least 1 stud every time I did it.

 

I actually took a look at the manifolds yesterday and the bolts, particularly the head of the bolts don't look too bad, are the stock manifolds on the 1GR-FE stainless or cast?