The mauser action will need to be trued and have a good trigger installed. The action may not be level so you may need a canted base or to shim the rings or use Burris insert rings. You will need a good stock.
The difference between a 240 Gibbs, 6-284, 6-06, 240Wby is small.
This is a 240 Wby with a 30 inch barrel and Joel Russo thumbhole stock.
If you wish to practice annealing some cases you read this thread. If you wish to buy a machine to do the annealing I believe the forum Gear shop sells them