Answer by
LeheckaG (1826)
Un-Plug ALL batteries/cords
(ESPECIALLY A/C-POWER)
from your-cassette-deck.
If your-motor-vehicle's dash-mounted-cassette-deck;
Then obtain (Chilton/Haines/OEM) car's-repair/service-manual for how-to remove/re-install cassette-deck.
Then carefully,
Use long-needle-nose-pliers/tweezers to grab some-coins.
Remove cassette-deck-case-cover(s) by removing the (usually-Phillips)screws & sticky-taping-them.
Over a clear-area/empty-box:
Rotate cassette-deck 360-degrees/3-axis to drop screws,
Repeat needle-nose/tweezers-grab,
Repeat until clear.
Reassemble (cover/screws/re-mount).