For those who have been waiting with bated breath...
The fat links from the 88 were a straight swap onto the 1990 model, same bushes and everything. The fat ones off the 87 (or may have been 86- bought a trailer load of leftover bits from a bloke) have a different diameter at the chassis end, require a different bush with a smaller bore.
The car drives heaps better now, whether that is because the bushes were shot (didn't seem too bad actually) or because of the bent lower link.