Hi Mr Wilder, Looks like you have got yourself in to a bit of bother.
Firstly did you do all the mods at the same time ? if so looks like you have several cans of worm's to sort out. Its time to clear your mind and start again. I had a similar problem a while back with a Pre Amp kit I built , I had an NPN transistor in were it should have been a PNP and my carrier is in electronics (Duh), it happens to the best of us.
A circuit diagram shoes how it is all connected up and you don't have to understand it unless you are the designer but some understanding will help during fault finding.You need to be-able to look at the diagram and find things on the circuit board to test. If your not able to do that I suggest you find some body who can help you out with that. If somebody came to me with your situation I would probably tell them its quicker to strip
it down and start again if multiple modifications have been added. Only do one mod at a time then test it before moving to the next one . This reminds me of my collage day's were we had to diagnose a fault with just a diagram and some voltages . I'll give you some pointer's to start with that may help.
You say in your post that you took out all the tubes out and got no voltages anywhere ,
if you take out the rectifier tube then there will be no voltages supplied to the circuit.
I am not being pretentious as how many of us have been testing for a power fault and one has not switched it on in the first place ( Put your hand up in the air if you have done this , there will be quite a few hand's in the air for that one)
We will start with the basic's
Safety first - you should be using an Isolation transformer to start with, if you are not then one hand in your pocket before you even start to test voltages, one voltage measurement at a time, switch off and let charge decay ( should be doing this any way don't care how experienced you are ).
Make sure you are capable of using a multimeter buy selecting the correct Volt's, Amp's Ohm's for the measurement you are taking.
PSU
We will start with the Power Supply. All voltages supplied from the PSU must be checked even if things are working (your post-" The lights on the meters came on" probably ?? getting supplied from F1, F2 Mains Transformer )
as this can create Red Herring's and lead to confusion. I would replace the chard wire you talk of as you may have to change later on as it has been stressed.
The way I would go about it is A,B,C,D as in diagram below , with Rectifier tube inserted. Disconnected were shown, Hand in pocket before Voltage Test's switch off allow to discharge for every measurement. As the PSU is effectively unloaded this should be done quickly but safely, watch that the voltage does not go above the reservoir capacitor max. voltage.
If you check all the voltages from the PSU and they are correct I would then connect B2 then B+ . If all is correct I start would measure the voltages on the diagram starting with the pre amp section. If all the voltages are incorrect (don't now if diagram is before modification or after modifications) then I would put it back to its original working state before any thing else.
This may be a lengthy process but that's what I recommend.
Never Give In , Never Surrender
Stay Safe
Will