Ron,
I have no idea what the addition of vinegar is going to do with what you said was already put into cylinders 5 and 6. That being said, you have less than a months time in this process of getting the engine unstuck. Patience and time is your friend if you really what to salvage this engine. AM sure others can vouch for sometimes taking much longer than this to try and win the battle.
That being said I would hazard a guess that if things haven't become "unstuck" by now, at least allowing even minute movement of the crankshaft, your about to the point of having to remove the head for further investigation and more drastic action if you are intent on saving the engine.
On your
Update...
There “appears” to be an inspection plate or something similar on passenger side of engine? Maybe not? ...
That is the push rod and lifter access cover. You can see your push rods, access lifters and such, but it does not give you access deeper into the cylinders themselves.
As with anything, your choice on how long you are willing to wait for positive results is your call.
IMO, I would opt for giving this more time. But I would also do what I could to clear out (suction) the fluid mix you know have and go back to adding a fresh acetone/ATF mix (my opinion).
If you not sure how to get the stuff in there now out, see about getting one of those big plastic kitchen turkey basters and a length of plastic hose. Use it like a bulb syringe to suck up whats in there. Will take multiple rounds to try and clear as much as you can. Don't forget to have a sturdy collection can to empty the baster into.
Good luck.
Dan
