Help me identify my gearbox

[ollieboy]

I have an 83 Corona with a 2T that has a four speed box. I want to put a five speed in but first I need the trans code obviously. The chassis number is TT140~ I think. Its NZ new so has some funny plate that I can't decipher, theres nothing clear that says T50 or W55 or whatever.

Your help is very much appreciated

Ollie

[fangsport]

is it all alloy or does it have a cast section between the bell housing and tail section?

alloy = T-40
cast W-40
as a rule of thumb with Coronas with a 2T