A500 overdrive (derived from the 904 based automatics) had a lockup converter from it's inception in 1988, however the A518 overdrive (727 based) did not receive a lockup converter until 1992.
You are correct, it's been over 10 years since I was going to do it and my memory isn't the best anymore, most of the info I got was for the 518 conversion and I forgot the converter difference.
I like the conversion kit that was shown in an earlier post, if it was available 10 years ago, I would have went with the 500 instead of selling it.
