The mods necessary??
For me they were, as I brought home a pair from craigslist with blown tweeters, which can be a common issue in La Scalas and Khorns. You will probably eventualy be facing blown tweeters at some point, so an upgrade will do you good!
Also my set were mid 80's models which had the undesireable AA crossovers, which could benefit from a rebuild. So after much recommendation here on this forum, I called Bob crites and talked
with him about options. Ended up buying the ct 125 tweeters and A4500 crossover and new mid driver washers , from Bob and have not looked back. I have also since made the bass bin mod that the speakers sit on and am very pleased with the La Scalas I am currently running. I really enjoyed talking with Bob and using his recommendations as they make total sense and work great. If I were to loose any other components on these I would call Bob crites again.
Just my .02
Gordon