I called Jim yesterday and he doesn't have any of this type of head to offer. He thinks it will be hard to find any but I am continuing to look around. if anyone in the forum has any to offer I am definitely interested.

Thanks for your assistance with this! 

I don't know...did you solder in your coin cell holder?
You checked it for continuity to the on-board circuit traces?
If you lose the internal accounting numbers and everything is reverted back to zero, then I would say that there's something wrong with the continuity of the coin cell holder mounting solder job than the voltage of the cell.
3 vdc is more than enough...I think you can drop as low as 2.78vdc, before the MPU shoots out a "Low Battery" message?
I don't remember the exact low voltage limit offhand, unless I look in a manual.
If you're NOT getting a "Low Battery" message, then something else is wrong.
Could be an MPU pin not getting a good connection, flakey power supply, or even the MPU itself.

Another thing to think of, is the machine works for about 6 hours.
Doesn't that sound like something is overheating?
How are all the fans in the machine?
Turn the power OFF and manually turn each fan you find in the machine with your finger or a pencil eraser tip.
What you are checking for is a fan blade that has waayy too much resistance.
The fan blades should spin easily and with hardly any effort - like as if they are brand new.
If the fan bearings are shot, that forces the PSU (Power Supply Unit) to try to keep up with the amperage to the fans to try to keep them spinning while under excessive loads.
After a while (in your case, 6 hours), because of the excessive fan resistance, the power supply gives up.
Six hours of old fans drawing too many amps - kills power supplies.
If you find a bad fan, then I'd be ripping the cover off of the PSU to look for bloated, swollen capacitors.... a definite sign of a PSU dying out.

I have a few of these units... complete with all the wiring harnesses and connectors.
PM Inbox me, if you have any documentation on them as to how to set them up?

The bell is supposed to only ring on jackpots

Are you certain the buzz you are hearing is coming from the bell?  The handle is locked by a solenoid, and it may be that - which you are actually hearing

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