a 98 frame should have adjustable headset, from memory is was 99 onwards the base 'E' model that didn't have it.
In 02 the fairing sides became smooth like the 998S and the R&G changed to suit. The battery changed on the bigger bike and sometimes that needs changing to smaller battery to fit the sliders.
Otherwise it should be ok. the bigger bikes got 12mm engine mounts
useful thread:
http://reviews.ebay.com/DUCATI-748-9...00000004031397