I want to thank SylvanLMP and Wallingford Plm+Htg for replying. I had the info from a pretty credible source, but one who hadn’t seen it done in years and whose memory of the product had faded, but knew of good results. While I see the pros of replacing this line, it has plenty of cons as well, including the fact that it would cause quite invasive architectural changes to the 108 year old structure. If it can be fixed I think I will try my luck and hopefully match that of my elderly friend and SylvanLMP.
L Edward Martin