If that guy could provide the AUX input on a short extension, one could mount it through the metal bracket for the cigarette lighter. It might be worth asking the cost to modify one’s own head unit. I like the company that fully upgrades the internals, but the cost for that service is prohibitive. A patched in AUX input might not be much better than a $5 cassette adapter, but it would be a little tidier and possibly better sound quality? And it could help folks that do not have a cassette unit.
SHORT BED 4-DOOR DIESEL: 1986 F350 4x4 under construction-- 7.3 IDIT ZF5+GVOD
STRAIGHT SIX 4X4: 1981 F150 2wd to 4x4-- 300 I6 close ratio diesel T19, hydroboost brakes, Saginaw steering
BIG F: 1995 F-Superduty under construction— converting to 6.9L IDI diesel ZF5+DNE2