Well, I thought the best thing to do was get a baseline dyno run, so I have something to compare my modifications with. I took my car down to the local tuning house (Motson's for those in Brisbane) and got the power figures and air/fuel ratio checked.
UPDATE 20/10/07
Got my car on the dyno again today. I went to a dyno day organised on the Twincam forums. I was hoping for about 100kW or so after all the mods to date. I was rather happy with the results..
After the replacement of the AE101 ECU and the larger throttlebody, the power drop is much less noticeable (although still there) and I gained a whole 18kW at the wheels.