I have also fabbed my own hitch carrier, and will be making another in the next few months. What Rick said about welding up a bolt together store bought model is sound advice. You will want the 2" class III receiver for sure. If you stay light and weld the rack up, you should be ok. You could also have a heavier wall unit made out of aluminum if cash is not an issue.
'99 UZJ100 Land Cruiser Locked with OME and BFG.
'94 Santa Monica Airlines 39" longboard, Indy 159s, Powell AT wheels
'14 Dodge 3500 6.7, 68RFE, Thurens, 5100s, 295/70-18 ST Maxxxxxs
'07 Adventurer 10T with surfboard racks!
'74 Airstream International 29'