Yes, the tranny is very rare. Did you get the 55 five window yet? Kinda funny, last summer I bought a 54 five window Chevy 3100 with a 4 spd hydromatic from Oregon. That was the first year Chevy put the tranny in the 3100. The local 'ole timers will gather around it, comment they've never seen one, but only heard of the automatic. It was also rebuilt about 18 years ago and parked ever since then! After we trailered it home to Idaho, I spent about 30 mins converting it to 12V, another 30 mins later we fired her up! She's a true survivor and I drive it a few days a week. The 4 spd automatic operates without issues. My 16 year old daughter loves to drive the oldie. I hope you get the 55, you'll enjoy it.
