:-)
in general, you can't even take a reel or hopper unit from another 809 and plug it in unless it's exactly the same model.
Bally made hundreds of variations of the 809. The model could be as simple as 809-A, longer like 809-ZZT, and when they ran out of room to insert Z's, they went with something like 809-9ZT.
hopefully you still have the model/serial number plate on the outside of the cabinet below the handle ... and it's correct. Occasionally people would remove it, repurpose cabinets to make a different model, bodge together a complete machine from pieces, or just attach a serial number plate from a not-even-the-right-model game for the same reason people change vin numbers on cars :-)
when transplanting units, the main thing is the payout counter on the hopper unit needs to match the reel wipers/contact plates, but there's other differences that can result in the plug connections having different numbers of pins so you can't even plug a unit into the cabinet.