91 Caprice frame off rebuild

So the decision is to do any possible upgrate, but to keep stock ECM. I know you can buy chip, or can burn it by your own, but that is a tone of gas for ceck and burn again and result could still be negative. As well, I'm living at Ukraine and to find good shop for burning the chips for US cars is rather problematic.
So will go with double exhaust, long tube headers, heads will leave stock (maybe will work a little on a swirl port), stock intake, cold air intake and will swap to electric coolant blower.
Before getting body off had to work on trans crossmember as till 93 crossmember were done only for single exhaust.

Few more pics

Ok, now getting all out from body and getting off the body.

As rebuilding will take 2-3 years, have to store each bolt. This takes more time, but no other choice, otherwise will brake my head when getting all parts back.

Now getting all from the frame

The frame is really rusty, especially rear side. You guys will surelly scrap such frame, but here in Ukraine I have no many choices, thus decided to keep and to work on it.

So, the only chance is sand blasting. But rear side is really bad and delema is how to clean rust inside the frame. There is a special nozle for sandblasting which is blowing not ahead, but around the nozle (it is used mostly for pipes cleaning inside the pipe), but all sandblasting shops close to me have no such nozzle.
For this reason i used electrolitics, using caustic sode (you call that waka soda). Here how it works: https://www.youtube.com/watch?v=2FkuptDnTS0
The result is very nice, on pics before and after.

Before sending frame to sandblasting made some reinforcement.
Started from the places where body mounts. As you know these are the weak places due to heavy rust. Mine were ok, but anyway decided to weld them a bit.
Got a washers (5mm) and wilded them on.

Now the back side, as you know frame of our cars do not really hold well, especially rear end. I know that you are using towing hitch, but I decided just to weld the piece of channel. Before that, had to reinforce the place where to weld channel.
Made it to look like wagon type caprice. On wagon frames, the end of frame is little wider, at the place of last body mount.

And now welding channel.

As well prepared few pieces of steel to weld the center part of the frame.

Now all done. Frame was sent to sandblasting and got it back next day.
Finally can see some movement in my job, these helps to continue working on same way.

Welded last reinforcement before painting.

Painting.
Most of you are using POR 15, unfo we have no POR paint in Ukraine, and I do not want to wait 3-4 weeks if to buy it in USA. Thats why I used 2 component primer and 2 component paint.
I've been a seaman before and on the vessels we vere using Hempel marine paint and primer. That paint keeps very good, working well against sea water and all chemicates which guys were using for deck washing.
Found such paint locally for good price (arr. 8 usd per one litter).
2 coats of primer.

Few more pics

Btw, was looking for a long time the way how to paint inside the frame.
Finally had found the gun for "gravitex" (not sure if the name is correct, and if you have same in USA. Usually it is used for applying at under the body, when dry it looks like a rubber).
This gun is chiep, as well made one more nozle for it to use for light paint, but finally was no need as original nozle holes were enough.

2 coats of black 2 component paint. Starting from inside the frame.

And outside.