Not sure whose good for halfcuts down there, I got mine from a shop up here (High Tech Tuning) who know their stuff and have actually been to Japan and source quality halfcuts.
 
I've had mine for over 2yrs and the biggest problem I've had was a broken a/c belt (touch wood).  1990 is fine - mine is 1990.  You do need to either change the cluster (to electronic) or change the pick up in the gearbox as the gen 3 gearbox is for the speedo is electronic.
 
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timjon94

Thanks so much man!
I just need to source a decent gen 3 halfcut..
it wont matter that mines an early mr2? (1990)

ahh i see, so if i buy the trd gen 3 mr2 cluster it should be okay?

Yep - get it through Gorilla Industries, and you'll need to run a few wires to it from the ecu.  (The pickup sends it to the ecu and the ecu sends the signal to the cluster.) 
 
While your at it, don't use the stock intercooler - buy a quality sidemount one as its easier to install with the engine out. 
 
Make sure u use the Gen 3 shifter cables off the halfcut (they are slightly different length to N/A ones) and try and source a gen 3 gear shifter - it probably wont come with the half cut.

Cool man thanks!
what do you think of boot mounted intercoolers?

Road and Track in Ipswich may be able to help.

Should be able to pickup a half cut for 2.5K - 3K
Mine was about that much from SSS here in Sydney.
Replace all the rubber seals too! and take the rear cross member off the half cut too!
Though some here don't like to use the newer rear cross member which makes the car more stable or 'pacifies' the rear during corners.
 
Good Luck with the conversion! very much worth it imho.

thanks man! cheers for the info