Whilst I wouldn't say a T1 is old, you might find the readily available spares can be taxing on your racing time. Open mod is on the other hand very tough on cars. You'll need lots of spare drivetrain components to keep the car running through a weekend of racing. If you're good with your hands and imagination though, you might be able to adapt a lot of current parts to fit your car though. If you've got the nitro style hubs and associated driveshafts though, they'll be a pain. Another point is you really need the new ECS driveshafts if you're going to use a front spool (which is pretty much the standard in mod). Without those, you're bound to have a lot of grief with the front end transmission.
That being said, with patience and a lot of inventivity, I think it can be done. Money will help though.