Andrew,
Give it a few days for other people to check in before you DO anything. There are some VERY knowledgeable people on this list who know far more than I do. Spend your spare time studying the schematic for the horizontal section and where things are on the board. And most importantly, what the voltage levels are at various points with particular attention to anything over 50 V. Then start with the easy stuff and keep going until you find the actual problem. Trouble shooting is an art. The thought process is the same no matter what the particular technology or context. It's a very valuable skill.
I tossed in the bit about rubber gloves without any factual basis. Probably a bad idea as it might give a false sense of security. I never wear gloves for anything if it's reasonable. So for HV I just made damn sure I knew what not to touch. Insulation is a function of both material and thickness. So there is no blanket answer and HV gets weirder the higher you go. But I'm old enough that to remember when everything I saw had tubes and there was a self service tester at the drugstore. I also blew up an AC/DC tube radio by connecting a ground when I was about 12. It *really* helped me get those late night long distance AM broadcast band stations. After I got a new radio. :-)
HF ads have coupons for free screwdrivers, DMMs and other stuff. Keep an eye out for them. A complete crap screwdriver with a resistor and alligator clip will do just fine for discharging caps. There's no harm in just using a junk screwdriver without the resistor. Unless, of course, you melt a push on terminal so the lead won't fit, Then you have something else to fix with a file. You can avoid that by making contact with the potential HV source first so that the arc is to ground. And lots of people have habitually used their good screwdrivers by making sure the arc was not at the tip where it could cause damage.
If your Fluke doesn't have an hFE test, the HF DMM suitably modified will do nicely for basic transistor function tests. I've got a better meter, though it's not a Fluke. But most of the time I use the HF units. I've got lots of them and often not interested in getting an accurate answer. I don't care if the meter says 110 V or 115 V. All I care about is that there is line voltage present at that point.
Have Fun!
Reg
