I've seen a number of different ways of "floating" the ground on computer PSU's when running them in series or parallel. I've had success by connecting a 120v power line w/o a ground connection as floating the ground.

on one unit that I intend to use, which is different than a standard PC PSU, the interior PCB is removed from the outer case and nylon stand-offs are fitted between the board and case and nylon screws are used to connect the board to the case. A standard 120v power wire is then used but since the case is grounded and nothing metal is touching the case, the unit is floated this way.

In either case, connecting the devices in series is done the same way.

I am wondering if either way is better than another. I would much rather use the removed ground wire than all the nylon standoffs and screws.

If pictures or model numbers are needed I can supply them if needed.

 

PC PSU are direct-to-mains SMPS (switch mode power supplies). The chassis is grounded to earth ground.
I would advise not defeating this safety ground. Hence do not connect PC PSU in series.

 

The ones I have seen the service ground is connected to the case, and the DC output is also connected to ground, you can often isolate the DC side from ground by lifting or isolating the connection.
The service ground should remain.
Max.