Hey Barney,
Sorry to hear of your problems with the US Gear EB.
The only thing under dash should be the control module...small circuit board inside is serviceable/replaceable. Sound like that was changed out.
The comment about taking it out every year to clean.......HA!
Mine hasn't been out since install 7 yrs. ago and if it comes out it will be for repairs not cleaning.
When you and mechanic had it out and couldn't replace bushing WHY re-install. Muffler shop make a short pipe :H
I wouldn't have it back in if it didn't work.
Mine has been flawless.