Gaensler et al. (1997) is maintained throughout, with two bright regions on the east and west sides of the rim.

Model Fits to the Radio Morphology
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Gaensler et al. (1997) showed that the size of SNR 1987A could be quantified at each epoch by approximating the morphology of SNR 1987A by a thin spherical shell of arbitrary position, flux and radius. The best-fit parameters are found by computing the Fourier-transform of this shell, subtracting this transform from the $u-v$ data, and then adjusting the properties of the model until the corresponding $\chi^2$ parameter is minimised (see also Staveley-Smith et al. 1993b). Using such an approach, Gaensler et al. (1997) were able to show that the radius of the supernova remnant increased from 065 at epoch 1992.9 to 068 at epoch 1995.7, corresponding to a (surprisingly low) mean expansion velocity of $2800\pm400$  (assuming a distance to the supernova of 50 kpc).

Here we extend and expand on these attempts to quantify the changes in the radio remnant. We first fit a spherical shell to all subsequent data-sets. The resulting radii are listed in Table \[tab\_9ghz\], where the uncertainty in the last quoted digit is given in parentheses. A fit to 