Not sure where the questions are but anyways here goes.
Never got into the 80 series Crowns - they were absolute rust buckets and most were SEs - locally built and spartan pieces of shit - pretty sure they ran a Bog Warmer diff. If you can find an 80 series Super Saloon you might get an F series diff out of one of them but it'll be a single spinner.
F series is 7.5".
LSD from an MA61 FTW. You could use a Torsen from an IS200 with a spacer plate for the crown wheel, if that tickles your fancy. TRD do a centre for them too.
Just use a W50. Only you will know the difference.
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