"Espo" are pretty good at holding their arch.It's been a year and they hadn't changed.I installed my replacement perches today.
Basically took some 3 1/2" square tubing with 3/16" wall and cut away everything that wasn't a spring perch...then drill the main hole higher so the car sits lower.It's 22" to my wheel well now and stock was 21 1/2"...close enough.