Yep. its a pita, but worth it.
several options as far as presses. mec makes a 3.5" press conversion, or you can buy a steel master press fitted for 3.5 from the factory.
I swap parts for my 600 from 12 gauge and 10 gauge units to make the 3.5" shells.
another option is to get a sizemaster, a roll crimper punch and a drill press.
resize hull with the sizemaster, knock out the primer with the punch, insert the primer by hand then seat using 1/2 in round stock in your drill press chuck using it as an arbor press. load using known good data use an overshot card and roll crimp to finish. Primitive, but it works. Obviously if you have a shotshell press already some of these steps can be done on it.