Some good news about a shop..I recently had an overhauled DG
installed. During the install, the tube/hose to the AI was
bent, hence the AI didn't work. Shop repaired everything the
next day, no charge. Turns out the replacement DG was a problem,
shop replaced *that* one immediately, no charge. And, since I
had to leave it overnight (and my car was 30 sm away), one of
the shop people gave me a ride to the rail station (I live a block
from the end of the rail line).

When it's your tush 2-8K AGL, that $5-10/hour difference in shop time
all of a suddent becomes irrelevant.