The 3spd (on the column) saginaw in my 64 chevelle just gave up yesterday. It still drives, but it makes some awful noises in first gear and pops out quite a bit. As this is my daily driver, I have to do something about it somewhat quickly. It made me start considering putting a 4spd muncie now that I have to change it anyway. I've done a lot of research on this site and have learned a lot, but I still have a few questions. Are all of the pre 71 muncies a direct swap for the saginaw I have now? Also, where can I find a new 4spd tunnel? Is the tunnel different to fit the tranny or the shifter in the floor? I've heard a lot of mention of it and some pictures, but I don't know where to find one. My car has buckets, what shifter should I go with? If I change the tunnel for one without a console, does that mean I can't add one later? What else is involved in the swap that might not be really obvious? Thanks!