Perhaps there are better methods but I've found that a hands-on approach can be very effective. The strategy is to get your pet used to fact that it is going to be handled whether it wants to be or not. Once your pet gets used to being handled in frequent short sessions it will become calmer and less likely to be aggressive. He may never actually crave attention from you or come to you to be removed from the cage but in my experience I've found that if you handle your pets every day they'll be more likely to come to you for attention. It will depend on the animal. You should see significant improvement in about a week if you use this method. I had one really aggressive pet store chin that responded well to this method.
If your pet is okay with being touched and petted then try to pick him up. Otherwise you will need to go in stages. Make sure you have some form of bond with your pet before going to this step.
You'll need to prepare yourself because it won't go smoothly the first few times. You may actually be bitten. Hold your pet securely and press it against your chest for about 15 seconds and then return it to its cage. Do this about 2-3 times a day. You can do it more often once your chinchilla get calmer about it. The trick is going to be to do this without injuring your pet. Don't let go if you get bit. Release your pet at the cage floor level. You can steady your grip at the base of its tail (not ever further up on the tail) and I highly recommend using the base of the tail as much as possible with your other hand under the back feet. You can even dangle your chinchilla from the base of its tail to help you get control if it starts getting squirmy. Be careful because chinchillas can slip their fur and it will come out in large clumps and make it very difficult to maintain your grip otherwise. Don't let your chinchilla think that if it bites you it gets let go. Do not let your chinchilla flail around in your hands. If your grip is loose enough to allow that to happen injury can be quite severe. Make it either all or nothing. Dropping your pet onto the floor or onto the cage floor from any height can be dangerous. Keep everything at floor level until you have a good hold.
Also prepare for the possibility you will accidentally drop your pet. If that happens you'll probably end up chasing it. Have a way to chase it out from under furniture safely. It can help to close doors to rooms that you really don't want to lose him in. Because you have experience handling the other chinchilla I suspect there will be a faster learning curve than the one I had but I warn you untamed chinchillas can be very challenging and fast as lightning.