I found a tube preamp that I was thinking of building and it calls for 150v for B+.  Can I rectify my 110v from the wall outlet to DC and use that?  Do I need to actually build a power supply using a transformer?

I am finally getting around to finishing up my Lm3886 kit.  I have a transformer from a home stereo i want to use.
First off can I do that, secondly how do I know what wires go to my power supply board.  I have the 2 ac input wires and there
are 5 wires from the secondary side.  There are 2 reds and 2 blues and one black wire.  The AC voltage varries depending on where I'm measuring from.  Where should I be testing and what should I be looking for?  Thanks for any help.

One of my Marshall's is an AVT50. I bought it new and less than a year into having it I fried a resistor and had to have it repaired. The repar guy said the fan quit and the output transformer got too hot and cooked the resistor. Recently (its been about 9 months since the repair) I smelled a burning smell again but havent noticed any huge performance issues. Last time the sound crackeled a little bit and slowly got worse. Now on to the LED part of my question. I have noticed that If i take a fuzz pedal (fuzzrite) and turn both knobs all the way up two of the LED's inside the amp on the board light up. I am assuming they are just being used as clipping diodes and that I'm driving the preamp pretty hard and its sending enough volts to light them. I can turn the volume and gain all the way up on the amp and they wont light. To me the amp is starting to sound a little weak and was woundering if what i described my have damaged something. I still have warranty on it but I dont want to take it in again and be without it again for a month unless there is something obviously wrong with it. Ok I'm out of breath. Any ideas?