No, I don't have any prior experience with this swap. I was just crusing the forum looking for some options on a different trans for my 51 F1. I read your post and wondered if you ever found the solution to your inquery. My 51 6 cylinder has that 4 speed crash box trans in it. I need to find a syncro trans to replace it. Its just to hard to drive in todays city traffic, especially in this area. Is that 3 speed trans you have from the 49 a syncronized type trans. Or were all the Ford truck transmissions in that day of the non-syncro type.

Rod