Been on the search for a 5 speed to put in my 77 620, which currently has an L20 and 4 speed combo. I came across an ad for a complete 1982 z24 and 5 speed transmission for sale for a decent price.
I've been trying to find info about using this trans and this quote below from datzenmike was good info. If I'm reading this correctly you use the L20 bell housing from a 5 speed on the napZ trans to correct the lean angle. Can I assume I can also use the bell housing from a 4 speed as well?
"The KA or the Z series transmission will physically bolt to an L series motor BUT it will be rotated about 20 degrees to the right with the shifter in the passenger side seat. the rear transmission mount will also be tilted and not bolt up. Not a good idea. You can take the front case half off an L series FS5W71B and swap it onto the KA or Z series transmission and this will 'convert' it for use on an L series motor. Keep in mind the the transmission doesn't care what clutch you use. It has no effect what ever on the transmission. The clutch used it totally dependent on what flywheel you have. Car L20B use 200mm bolt pattern while trucks use 225mm. The flywheels look the same it's just the pressure plate mounting bolt pattern that is different."