Adding line out for recording?

I was looking at a Matchless Lightning schematic the other day and saw that the line out was just a jack with a 20K resistor across it and perhaps a second line resistor. Is there any reason you couldn't do the same for a Music Man? Allowing for the difference in power from the 4xEL34s, of course.
Mike

well my friend has a line out with a level knob
and an effects loop
on the back of his HD130
so its possible but dont ask me how to do it!

If you don't feel like "engineering" your own solution, you can buy an Effects Loop/Line Out kit from Torres Engineering on the web. Also, a simple Line Out was described in Vintage Guitar by Gerald Weber and I think this method was repeated in one of Gerald's Tube Amp books.
Line out by itself can be pretty simple, and you need to decide whether it is best to grab the signal BEFORE the Master Volume control (so the Line Out level is not affected by changes in output volume settings) or after the Master Volume control (if you want to control the room volume AND Line Out at the same time).
Depending on where you grab the signal, it may be necessary to use a solid-state device to "buffer" or isolate the Line Out connection so it will not interfere with or adversely change the sound of the amplifier. This why most amplifiers use active stages (semiconductors or tube halves) in installing Effects Loops.
Remember, a Line Out is basically 1/2 of an Effects Loop. Look at the schematics for the RD-series of Music Man amps. They have two front panel "Insert" points on the front panel that are essentially 2 effects loops ionserted at two different points in the preamp circuit. Not only do you get two different signal levels, you get different amounts of circuitry before and after the Insert point.
Steve