Help needing paint stripped on a 2333

Acetone

Is it going to be custom painted? From what I have seen/heard the early black plastic used for the 2333, 2343, and 2344 doesn't hold paint very well. Your friend may be better off finding other shells in better shape. 

Rubbing alcohol or denatured alcohol will both work. Both are flammable.  Acetone is too aggressive and will dissolve many plastics.  Not to mention it has a high vapor pressure and a low flash point, not a good combination. Would be my last choice.   I use Lye, sodium hydroxide which is the active ingredient in oven cleaner.  In an old 5 gallon sheet rock mud bucket I add about 4 gallons of water and 1-1.5 cups of lye crystals stir till dissolved.  Tie a nylon cord to the body shell and lower into the solution, every 6-8 hours scrub with a soft nylon brush most paint will be off in a day or two. I keep the snap-on lid on the bucket while soaking.  Use rubber gloves and eye protection though this weak solution would give you plenty of time to rinse your eyes with running water should some splash in your eyes.  Old clothes !    I use a brand called ComStar Commercial Lye that a small independent hardware store near my house stocks.  $6-8 for a life time supply. Once all the paint is off wash well to remove all the stripping solution.  The old Lionel shells hold paint just fine but the new water based paints don't stick very well.  I scrub my shells with a soft brush, soap, water and a lot of BonAmi scouring powder. till all the shine is off the plastic.  Now you have enough tooth that most paint will adhere.  I have a stock pile of original Floquil model RR paint it is no longer made and works fine on the Lionel F3 shells.  I use Floquil's water based PolyS paint but don't like it quite as much as the old solvent based stuff.   Forget using spray cans you will never get the paint on thin enough not to hide much detail.   I have been known to spray out of a can into a jar and then use it in my airbrush.  That is the only way I use spray cans on models.  There are infinite ways to get your F3s a good new paint job this is just the way I do it.  BTW;  The lye solution will strip the remaining chrome plating off old chrome plated cars, such as the Flyer passenger cars.   j

Try to  get the 95 to 99% alcohol. Rub  in onto the inside of  shell and see if it recks the shell if its plastic. It its metal there will be mo problem.