There are minor different versions of the board over years of Fiero. Example: Some actually have contacts for 1 or 2 "spare" bulbs hidden by front of dash. (2 blank slots above the tach lights.) The big plugs just isn't wired to use them.
84 Dash may have more changes the others.
Worse Most to all FSM and other docs are wrong what plugging into it like most/all is missing 2 "dimmer lights" lights to light fuel and temp gauges w/ HL on.
So can't trust data there.
"Board" is single layer but w/ plastic over the copper too. Is done to protect the copper and prevent shorts.
Replacement "boards" can have same problems of OE boards or worse. Many Fiero dash trim are missing foam to block UV from sun. Many plastics and "glue" won't last long when true. OE dash gets baked and UV and other pollution to deal with and it's a wonder last so long w/ only minor problems.
Another problem is the plastic "board" and dash case can "compress" over years and part of many bulb sockets have problems even when the sockets are replaced w/ new ones. If you just slap a new board over old case then could have problems very soon as new board conforms to old case plastic.
I think OE "board" copper is thicker then normal. Maybe 2x or 3x the thickness of most others even flex "boards." Is why can survive "bad glue" for the big plugs.
"old way" to spec a board copper is X oz copper per 1 sq/ft... (or maybe 1 sq/yd not digging thru my notes...)
most standard boards are 1oz or less.
Might be this is 1.5 to 2 oz. Maybe up to 3oz.
Board base plastic is thinker too then nearly any others flex boards I seen in 40+ years of dealing with them. Between case plastic, thick board plastic and copper all adds to make clearance etc for bulb sockets and other parts to fit right.
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
The Ogre's Fiero Cave