Hi Jon
I sent you, amongst the many, many files one called Complete Rebuild Slide Show.docx. Look for that
PL400 Assembly Process Slide Show (Adobe Acrobat)
PL400 Assembly Process Slide Show (PowerPoint)
The PL4000 will be your weak link. The design was a first attempt. They learned from it and did better on subsequent products...
There are much better pre's to pair up with a PL amplifier.
The latter...
I have an SE variac. Great American quality. I got mine for a song since the outer wrapper was slightly dented. A few minutes to make a wooden last in the circle shape and it was back to looking brand new again. Good luck with yours Jon