I have a similar background and experience to you but I also make custom guitar amps so the latter has helped.
***** It is the experience with working on guitar tube amplifiers that gives me the confidence that I can restore the electronics ofan old juke safely
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PLEASE NOTE THAT LETHAL VOLTAGES ARE PRESENT IN THESE CIRCUITS****
Here’s what I did when I restored my 100C.
Before plugging it in and applying any power…
1) Bought the following
very invaluable books:
• Seeburg Service Manual M100C
• Seeburg Installation and Operation Manual M100C
• Seeburg Mechanism Guide 2nd Edition by Ron Rich
• Restoring the Seeburg C by David Cooper
Read these many times and refer to the appropriate sections in the course of the restoration particularly when restoring the mechanism.
2) Search the ‘net (forums, Youtube, Facebook, restoration blogs etc.) for any reference to the 100A,B,C (or any Pinbank 100 selection models – as they are all very similar). Bookmark for future reference.
3) Took the 100C apart into its various components: Receiver, electrical selector, mechanism and pinbank, speaker and amp.
RECEIVER4) I started with the receiver with the rationale that I first needed a reliable power source;
** Checked the fuses
• Inspected the line cord and all the wiring,
• Replaced caps and out of spec. resistors.
• Cleaned and lubed credit unit - cleaned switch contacts and checked gaps.
• Cleaned and lubed the stepper unit - cleaned switch contacts and checked gaps.
• Tested the receiver using a current limiter (lightbulb in series with the line cord) – note: it’s the first time I applied power to anything.
• Check and verify voltages at various points in the circuit
ELECTRICAL SELECTOR5) Cleaned and lubed the electrical selector.
PINBANK6) Removed, disassembled the pinbank (Restoring the Seeburg C by David Cooper and a Facebook pictorial
https://www.facebook.com/media/set/?set ... 259&type=3 was helpful) – this can be daunting – but the pinbank has to work reliably so it’s worth the effort in my opinion.
MECHANISM7) Disassembled the mechanism, cleaned the mechanism, switch contacts and lubed as per manual and Ron’s Seeburg Mechanism Guide

Adjusted the switch gaps as per the manual.
9) Assembled Receiver, Electrical Selector and Mechanism and tested, adjusted until every selection worked reliably.
AMP10) Removed all tubes and re capped amp and replaced out of spec resistors.
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I REMINDED MYSELF THAT LETHAL VOLTAGES ARE PRESENT IN THESE CIRCUITS****
11) Connected amp through current limiter (lightbulb in series with power circuit to amp) to receiver
12) Plugged in speaker and applied power
13) Checked and verified voltages at the various test points indicated on the schematic then systematically plugged in tubes and measured voltages.
14) Played selections
15) Cleaned, lubed and adjusted the colour cylinder mechanism.
16) Cleaned coin mech- adjusted coin switches
17) Addressed the cosmetics of the cabinet.
18) Reassembled the 100C –Putting the mech, amp, receiver, service switches, speaker back into the cabinet.
Some things that I’ve learned in restoring pins and jukes:• Label caps, resistors, tube sockets etc. relative to the schematic as I re-buit the amp and receiver
• Take pictures – I can’t go by memory
• Deoxit (or equivalent product) on every contact
• If I need a view of the circuitry or mechanism where I didn’t take a pic, the internet (even eBay) will have a picture.
• There’s no rush- this is a hobby for me.
• There are people on this forum who really know their stuff!
Your mileage may vary but that’s how I did my “C” (and Wurlitzer 1100 and Rockola 418) and it (they) work like a charm.
Good luck!!