I can't finish the battery cable run till I get the engine installed, so I started back on the avionics tray.
Against the advice of Jim Ratte of Recreational Mobility, I installed the ELT at the front. PA is now placing the ELT up front on their electronics mounting platform which is farther forward than this avionics tray, so I think its not a problem. I did not want to place it on the boom tube and I could not find any place else to put it.