radio fitment
 

quick question for the sq body experts: I see some delco radios listed as fitting 73-87, but most I see listed fit 73-77 or 78-87. Was there a change in the fitment around 77/78 or will any factory radio from 73-87 fit any 73-87 truck? Thanks for your help.

Re: radio fitment
 

They should be the same as long as you put the old school turning knobs stereo

Re: radio fitment
 

All of the stock stereos and radios that came in these trucks should interchange with no problems using the original knobs. I've been driving these trucks and playing with them for 38yrs and I've never had a fitment issue.
Now I've installed a stock am/fm digital cassette out of mid 80's Old's and Buicks with a small adjustment to the dash tin. The radio face is deeper/taller than a stock radio so you have to trim about a 1/4-1/2" of tin on the dash of the bottom of the radio opening so that bottom side of the radio fits in the radio opening properly.
I hope that makes sense. You also have an extra wire to keep power constant for the radio stations and the clock. Some also have an extra wire for the electric antennae that some cars had.