Test deflection board without anode attached to tube?

[DirkDiggler_ESQ]

So, I replaced all of the caps on my U2000 (all are in the correct spot and all are oriented the correct way) and when I power it on, I get no display.  I can hear the tube power on, but nothing is shown on screen. 

I can't get to some of the resistors and other components that Randy Fromm suggests to check in his troubleshooting flowchart for this monitor with the tube in place.

Since you can't fire up the monitor without the anode attached, how can I get meter leads into the tight areas that I need to test? (other than "very carefully"

[Q*Bert_OP]

Don't power on without the anode attached...over 20,000 volts will come out of the anode...

[Ken Layton]

Some monitors have a "service mount" way of positioning the chassis for servicing. In many cases this involves sliding the chassis partially out and a heavy piece of cardboard or other insulating material is slid under the chassis to keep stuff from accidently contacting the metal frame and blowing stuff up.

There are also made extra long "grabber" test probe accessories for your meter that you could buy.

[DirkDiggler_ESQ]

I was able to weasel my leads in there and found out some interesting stuff:

The Good
TP200 is supposed to be 4.34 V and it read 4.04 V
TP201 is supposed to be .10 V and it read .14 V

The Bad
TP202 is supposed to be 127 V but it only read 107.6 V
TP203 is supposed to be 126.8 V but it reads 142.4 V
TP205 is supposed to be 32.50 V but it reads 22.86 V

Any idea what could be causing the over-volting at TP203 and the under volting at TP202 and TP205?  I checked R100 and got a reading of 5.3 ohms, but the specs for that part call for a 4.7 ohm resistor to be there.  Even with the 5% tolerance, I've still got more resistance than I should.

I also noticed a really loud whine coming out of the monitor that wasn't that noticeable before the new caps were installed.  Any idea what could be causing that?