Datsun 520 / 620 ?
Super cool man...
The rear leaf-springs will need some custom job.
But get a clean, good chasis with no rot, rust or rejoint.
It will be a very nice car to work on... Many many aftermarket compatible parts.
Can plug and play any A series Nissan Engine... A12 from Datsun 120Y or A15 from those Vanette Van.. Lots of torque.. (Can drift)
SR also can.. :D need engine mounting work..