"b" trans to "c" trans ??

does anyone know what it would take to put a "c" transmission in my 1985 ca20e with a "b" transmission.
thanks

What is the motivation for this swap? Are the ratios in the 'C' box better? I was considering putting the 'C' box I have into my Zcar, since I know the ratios are a little closer than the Zcar 'B' box. (requires using at least front half of Zcar case, and etc. stuff...)
Perhaps it's already been discussed, but what are the ratios in the stock S12 5speed? Those found in Zcar and S13/14 boxes are readily available, I can look them up if anyone is interested.
I assume the bellhousing pattern and starter location are the same between CA/KA/L-series engines?

the B transmission has linkeage, the C is internal. I think the C is also stronger internally.

Sloppy worn out nylon bushings with a long throw, or nice crisp shifty-shifts.

I'm pretty sure the ratios are the same

Maybe I'm reading you wrong, but the KA/CAs have different bellhousings, but from the bellhousing back are the same. I have no clue about the L. I heard the L grew up into the KA, so they might be the same ...

1st 3.592
2nd 2.057
3rd 1.361
4th 1.000
5th 0.821
reverse 3.657

that's for the turbo ... not sure, but I think the ca20 is the same.

Indeed, there is speculation on hybridz.org that the C is stronger, though I don't know what to believe. I'm going to disassemble mine and compare bearing, shaft and gear sizes with a caliper; if those are the same the only other variable would be material.
I asked about KA vs CA bellhousings because I assumed the C gearboxes you are discussing are coming out of KA24's. I don't know what else a C would come out of, if S12's have B boxes, except maybe trucks or a 300ZX (?). It is certainly an issue if there isn't a C box that bolts up to a CA engine.
I threw in the bit about the L engine because I have put one of my Z-car trannies up to the 240SX motor I have, and the bolts line up. Nissan leans their crossflow engines over the opposite way of their non-crossflow engines (i.e. L-series with the intake and exhaust on the same side) so the gearbox sat at the wrong angle.

I don't know what else a C would come out of, if S12's have B boxes, except maybe trucks or a 300ZX (?). It is certainly an issue if there isn't a C box that bolts up to a CA engine.
Midway through 1986 until 1988, Nissan installed the C tranny in the S12.

i have bought a "c" trans at a good price, and would like the ideal of being able to use a real short shifter, the trans i bought is for a ca block, so i know it will bolt up to the motor, i was not sure if a 85 trans mount and cross member would work on an 86 and up transmission. also didnt know if the drive shaft was the same or not.

Midway through 1986 until 1988, Nissan installed the C tranny in the S12.
Ah, you learn something every day :-D
You know, Motorsport Auto makes a short shifter for the B box for Z-cars. I think it works by having little extensions attach to the stock lever pivot, raising the pivot a bit. Never seen one installed so I can't comment on how much feel is improved, but it would have to shorten the throw by quite a bit. They advertise the percentage, I can't remember it off-hand though.

I would think it would just be a tranny and shifter swap.

Possably the drive shaft too.