You could just set it to flat and make a simple tone stack as a pedal to go in front of the amp.  That way you get tweak it the tone better without hurting yourself, and without a permanent mod to the amp.

For a single LM3886 a 160va should be fine.  I got the larger one so I could add another channel if I wanted to.

Indeed it can be internal.

http://www.ssguitar.com/index.php?topic=57.0

Or a boat prop.

If you like the heavy tone of it, go for it.  For a while I was playing on a 30w Fender Bass amp and loved it.

It's always a good idea to do research BEFORE building a project like this, so good job on that.  As far as a transformer goes, I recommend one of these:

Avel 25+25 250va toroidal http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=122-625

For the fuse I just used a 1 1/4" glass tube fuse.  Not sure how many amps it was...I think 3 amp.

On the topic of small amps, I love my Dean Markley K-20X.  I personally haven't heard anything with as great a clean channel as it, and it has a really solid overdrive channel.  To tell you the truth, its basically my favorite overdrive sound.

Never heard of anyone doing the lightbulb attenuator on anything other than tube, but if it works it works.  If you do it, be sure to tell us about it.

I'm not totally sure.  But isn't that an actual spring reverb?  Kick it and it should sound like a bomb went off in a spring factory full of PA equipment.

And I'm out of LM3886 boards.  LM1875 kits soon to come.  They should be about $10 a piece, but I won't know for sure until I place my order for the missing parts.  I'll keep you guys updated.  It's taking longer than expected due to an immense interest in the LM3886 kits as well as other projects keeping me tied up.

You should take a picture of it, I wanna see this thing.

From what I gathered from your post it shouldn't be a problem since you are running it from the headphone out.

I have 2 sets left, each set consisting of an amp board and a power board.  $2 for one set, $2.50 for both.  Paypal the money to joseph.raymond@umit.maine.edu

Do you have a schematic for it?  That sounds like a good idea to me.

I've been thinking about building a wah like that with the knob on the top just like a gain knob or something, that way you can have that "cocked wah" sound at any stage of it.