I would start MultiBeast, under "Quick Start" select 'Legacy' or "UEFI', then depress/push/select the "Drivers" tab, depress/select the "Audio" button, select the appropriate audio chip, say the AC1150 (if that is what your motherboard has) (and if it is not listed then I would leave everything unchecked),
then select the "Disk" button and if the motherboard has an Intel SATA controller then I would select that (and if it has an auxiliary (3rd Party) SATA controller [ASMedia ASM1061, JMicron 26x (GSATA), Marvell 88SE912x, 88SE9172, or 88SE9230] (check your mother board for the chip number in the specification page) then, and only then, would I "tick" (check on) the box,
then move down to the "Misc" button and check-on appropriate boxes for power management (although you can probably leave them all unchecked for now - and after you can boot in you can then re-run MultiBeast and tick on the power management options (plugins, HWMonitor, PowerManagement options [VoodooTSCSync is only for LGA2011 motherboards]),
then select the Network driver (you may want to leave them all unchecked and see if the NIC works (Internet access) after the first build,
then select the USB button and check-on 3rd Party, 7/8/9 Series USB Support, and/or "Increase Max Port Limit" for 9/100 series motherboards (a "100" series board would be the 170 series for exampkle, but a Z97 could be both a "7/8/9 series" and a "9/100 Series" board. You would install one or the other and see which one works, rebuilding as necessary,
then select the Bootloader, "Legacy" or "UEFI",
then select the "Customize" button, and
check-on any internal video controllers (Intel HD3000, Intel HD530), or Inject ATI (4xxx video cards), or Inject NVIDIA (GeForce 8xxx, 9xxx, 2xx, 4xx, 610 or 630),
then you probably wouldn't want to select any of the SSDT options (at least not until you know that the system works - in which case you would then re-run MultiBeast, selecting all the previous selections and trying the "Sandy Bridge Core i7, "Sandy Bridge Core i5," or "Sandy Bridge Core i5/i7 Overclocked" options),
then in the "Systems Definitions" section you may want to select a more appropriate CPU model (after seeing whether or not the MacPro 3,1 selection works and upon sub-sequent rebuilds of MultiBeast),
"But how do you find out what would be a more appropriate "System Definition"?
https://support.apple.com/en-us/HT201634 and
http://www.everymac.com would be a good place to start, paying attention to the CPU and the ID, then selecting the closest model. For example, an iMac 11,3 could be a 2.8G i5, 3.2G i3 or 3.6G i5. That's just an example.
A better table may be:
https://en.wikipedia.org/wiki/IMac_(Intel-based)
Now you're finally ready to "Build" the system.. You depress the "Build" tab and - MOST IMPORTANT - on the right side you select where you want it built, on what drive.
On the lower right you now hit the "Install" button.
If it comes up alright you will probably need to Shutdwon the PC, pull the USB, turn on the PC, hit your "Boot" key (usually F9, F10, F11, etc) and see if it boots (Clover should automatically select the HFS disk and boot after about 5 to 10 seconds).
Once you know it boots okay, and after testing the NIC, Sound, Video, etc., you may want to try different "System Definitions" to see if they "magically appear" after rebuilding it to a different MAC ID.
You may need to re-build it a third or 4th time, each time fine tuning it, like installing patches, changing IDs, etc. Yes, you would shut the PC down again and boot from the USB drive and then re-run MultiBeast.
