I have the same TV. Is this the cabinet you have? I got mine from a guy at work who built it as part of a correspondence course. It had sat not working for many years. I fixed it (blown rectifier diode) and it is my daily driver. It has the original electrolytics. Its had other problems - it would not color sync and also there was a problem with dirty pots, but it's been working pretty good lately. Also I had to replace that main circuit breaker with a fuse as that was shot.
There is a yahoo group on Heathkit TVs but they don't seem to be active lately.
https://groups.yahoo.com/neo/groups/...tions/messages