Ross, you have a couple of options, I would prefer people not switching chassis, even for a supposedly slower one.
(1) You can find a similar track to Wigram as Steve says and grab a setup for that then you should only have to adjust gears and cambers perhaps.
(2) You could download the Honda setup and rename it to become a Lotus setup. All you have to do is change the file extension from .mu1 to .lo1 and it will be a Lotus setup, though you will need to adjust the gears as the Honda has 6 to the 5 in the Lotus.
Your best bet by far though is to find a setup you like for any track and balance it how you like and then use it for every track changing only the gears and the cambers as you go. Then you only have to learn the circuit layout as you know what the car will do because you are used to it.
For option 1 you could try the Westwood setup you used as the circuit is not too dissimilar in layout and speed or maybe try one of mine, maybe the Watkins one.
http://www.jamesonline.net/gpl/setups_65.htm