[bikerhifinut]

Some good advice here for you from earlier posts.

I have a fair bit of experience with the leak El84 stuff and totally agree with the advice.

DON'T get conned by the people who will tell you that PIO capacitors and carbon film (crapon?) resistors are essential. I've been there and trust me, any difference ain't worth the effort.
next myth to bust................. These amps are perfectly fine with modern sources. Don't worry about their highish sensitivity it's really not that much of an issue. If you can hear too much hum etc you're too close to the loudspeaker!
The leak preamps are of their time but can be tweaked up fpr modern line sources. Myself i wouldnt nowadays do this as they are fetching stupid prices on the auction sites and i would hang on to it. they have a useful set of attenuating pots on their line inputs so its possible to use a point1 preamp with a CD player without overloading the first stage.
I use a passive job, thats audiospeak for a potentiometer (volume control) in a box and it works just fine and dandy, anything from 100k to 10k will work well with a modern source and don't get side tracked by people trying to confuse you here.
Or use a modern preamplifier. Some have adjustable gain but even one with the usual gain for a less sensitive modern power amp will work ok as a general rule. Again I have done this so I am not hypothesizing. Accept the fact that the volume control will be used at the quiet end of its rotation and its fine.
You've got yourself some lovely amps and I hope you grow to love them as much as i have mine.
for what it's worth, I would get the stereo20 fettled first. Then i would get the TL12's sorted out. Don't worry about cosmetics, get em right first. I reckon you'll like the stereo20 enough to think about moving the TL12's on and you might even make a small profit. thertes not as much difference as certain pundits would have you think.

Andy.