don't understand what the kero mix is supposed to do? If you don't want to see a detailed explanation, DO NOT read on, you may be wasting your time.
First my 68 RR was on a rotisserie so working underneath was easy. I made several air blow nozzles with copper tubes to reach back in the frames. I would tap on the frame (with a hammer) all over and then blow it out, and do this about 30 times. you will always seem to get stuff out of the frame sections. I would take the longer and shorter nozzles and bend them and insert in every hole and in each direction. be patient and keep doing this.
After it seemed to be cleaned, I got the green internal frame coating from Eastwood, and ordered some tygon tube from Mcmaster Carr (the same internal diameter as what comes with the Eastwood coating) and took the spray can push button nozzle from the frame coating can, removed the little tube that comes with it (had to slit it with a razor blade to get it off), and installed the longer tube on it. I also installed the small fan spray nozzle on the longer tube (about 4 feet long). I added one small drop of superglue to each end to keep the tygon tube from coming off. I then used the longer copper tubes I made for the air nozzles and taped the tygon tube to the copper (as a stiffner). I would insert the long spray nozzle and then spray as I was pulling it out. I did not skrimp on the frame coating and used about 7 cans, and did this 2 or more times in each section until the green paint was coming out. I also bought some "Pre-paint spray" from eastwood and would remove the push button from the frame coating can, insert it on the pre-paint and spray just a little to flush out the frame coating so it was clean and could be reused.
This was not a fast process, but I know this frame will outlast me many years (car will not be sold). so you need to make the decision of if you want to go to this level of detail.
The trunk floor was out so it was easy to clean and paint the rear frame rails. I also installed the frame connectors from US Cartool and sprayed them also.
As you may observe from the long write-up, I am an Engineer and I assume NOTHING, and always go overboard on anything I do.
Since my Roadrunner will almost never see any rain or bad weather conditions, I think the frame will last about 100 more years.
Let the clock and your pocketbook be your guide. I really think that there are only a handful of cars out there that have this much internal frame work.
good luck and thanks for your patience in reading this run-on explanation.
I really did this for others to see what the ultimate internal frame coating is about. I know a few people will like this but I also know some will think I have a real problem with detail. Donny (DR. Blast) will appreciate this as he and I are alike.
thanks
PT in Tennessee