i just finished building a suckthrough turbo setup for an L block bluebird.
the only thing i bought was a turbo and exhaust manifold cost me $300.
i used the standard inlet manifold just removed the carby and made a pipe that ran from here to the turbo outlet.
for the oil line you can just put a t piece into where the preasure sender screws in.
when i first put it on it blew a head gasket so i got a 2mm copper gasket made for bout $120
runs sweet now on up to 10psi
no reason why an A series wouldn't be any different
i should really take it to get tuned but havn't got off my arse yet