Owen_Dyneto wrote:
Based on my own experience and that of many other owners, I'd use Type F fluid which is believed to be the closest in formulation to the original Type A. Note that many users have also had good satisfaction with B&M's "TrickShift", and yet others have apparently had no problems with Dextron.

When you remove the pan, check it to see if the bolt holes have been distorted from prior overtightening. If so, use some flat steel and a hammer and tap the enlongated portion of the bolt holes back to a flat surface.

Too long ago to remember when I did that seal on my 54, but I do recall it was a simple job, I drilled two small holes into the seal, inserted a couple of short sheet metal screws for leverage, and just pulled it out.