I’m not the most qualified person on this board but I’m fairly certain that 5v is way out of range. The original rectifier boards are underpowered and well past their designed lifetime. I (and many others) replace them in any machine I acquire.
If you’re comfortable or want to learn putting together a very easy to assemble board: https://nvram.weebly.com/bally---stern-rectifier.html
Or an already assembled (with bonus for new connector pieces included): https://www.pinballlife.com/mm5/merchant.mvc?Screen=PROD&Product_Code=PBL-100-0070-00
Either will still require soldering them to the transformer.
You could also remove the high voltage needed for the plasma displays from the equation by installing new LED displays.