The '93 AfricaTwin is type RD07, i used to have one (i now have a '97 RD07a).
There are no big technical differences between the RD07 ('93-'95) and the RD07a('96-now), They all have the tripmaster.
The suspension is different: The RD07 has airsupported front forks (with airvalve) and adjustable rebound on the rear shock. The RD07a is not adjustable (only preload on the rear).
The headlight-fairing and windshield are different and the seat is supposed to be improved... after 35.000km on my RD07a i still haven't noticed how...
As far as i know the RD07 models are less likely to have fuelpump problems aswell, mine had 75.000 on it when i got a nice Suzuki Alto bumper print in the side, and the pump never failed me. On the RD07a it allready died twice (!)
You can get loads of info on the AT at: http://www.atic.org/
(very active forum, in German)
Hope to have helped you a little, the AT is a realy great bike!!! You can do allmost annything with it!