[Roadsters] Transmission interchange question

[S B]

After almost a year of being off the list I'm happy to be back.  I've got a
white 66 1600 thats pretty much stock.  I'm considering rebuilding or
replacing my 4 speed transmission, even though its still working fine.  Is
there any information or website out there that has a list of transmissions
that will bolt up to the R16 engine with minimal or no modifications?  I did
find a great site that gives details on installing a Mazda Miata
transmission.  I'm just looking for what my options are.
 
Steve