the internal ring I have no clue what it was out of, or if it was machined.I know of a guy that can do it like that, but its not cheap or easy to do and has a few down falls.
freestylemike@hotmail.com thats his email, nice guy and has a good rep.
the external tone rings can be done a few way's and depedns if you have a 2 pice or one piece drive shaft.
curt leduc ca prefun 909-845-8820 has one for the fullsize trucks that uses the flange off the t case as the tone ring. this is the nicest one, and may beable to get them to do ones for rangers if they get the call....worth a shot.
runs about $300 from what I understand.
BTF fab has started making tone rings as well, and was working on a kit as well.PH# 909-702-7462 these will work on once pice driveshafts and they are pretty smart guys so I bet they could get it to work on a two pice also.
Tony from trueline.com 619-258-1800
http://www.truelinewheel.com/map_e.asp
also has a tonering set up, that will work with the 2 pice drive shaft.
brea automotive also has a tone ring set up,
http://www.breaautoelectric.com/products/products1.html
Have heard of some problems with this one awhile back when they first came out and they were the only ones on themarket, thats been about 6 years ago though.what I heard was the "tone"was off on them,but better than nothing. like I said that been six years ago.So I would think they should have that fixed by now if it was so.
Most all the info on this stuff has come from the desert truck boards.But there is really not much info on them. Other than who has it etc.
the only one I have ever dealt with was the leduc one about 3 years ago on my buddys bronco, worked great for the 20 miles he had it, then the bronco got stolen.