the bigger issue is to how to "safely" get the blades off, without a ramp or something to raise the deck high enough to get a fuel or impact and the correctly sized socket to the hub bolts.
IIRC, the exMark is about an inch or 27mm bolt...I usually get them in the shop when someone has used a pipe wrench with two feet of kendorf or a pipe on the handle....or buzzed the corners off with an impact.
Now you need some tools...
best of luck. BTW, we ended up putting the machines on a 45 day maintenance plan where we just took blades and bolts from the shop out to the machine, replaced them and brought the "dull" blades and wonked up bolts back to the shop for sharpening. It turned out to be much cheaper time and effort, to have one guy responsible to NOT mess up three bolts and be down a day (or more) waiting on a part or a fix. HE kept the correct tools, washers and bolts and blades.