[Amps] Alternative input network Upgrade for SB 220

[Patrick Barthelow]

Friends, 
Somewhere I saw a  3 -500Z input network aftermarket kit  that was a long narrow board with the coil/cap combos mounted side by sideon the board, and available for 3-500Z or perhaps SB 221  installations.
I did not see it at the Harbach website.
I received a very mangled SB 221 input network that I am trying to fix, and having extreme difficulty due to the age, and density of mounting   the cardboard coil formers,  making them brittle, and subject to easy breakage if disturbed in the process of removing and replacing all the silver mica capacitors, that were all assembled and soldered in sequence to a central grounding terminal.   I have heard the 35 year old coils are sometimes troublesome if any need to be tuned by the internal slug positioning, sometimes breaking in that process too.   It is exceptionally difficult to even read the values of the SM capacitors in situ.   Any input network packages out there?  Tnx, 73, Pat AA6EG