So 40W into 50ohms is Vrms=sqrt(40*50)=44V. Vpeak is thus 63V (or 126V if it wasn't terminated in 50V). Ought to check that's OK at whatever frequency you were using. If course if you were using the scope to dissipate 40W in its internal 50ohm terminator, that might well be toast.
Possible mistake of mine: ought to check if the 2465A has the problematic capacitors on the A5 board; it might be only the 2465B. Even if it is marked as a 2465B, you might care to check the A5 board, since apparently there's an infamous fleabay seller that <cough>upgrades</cough> 2445Bs. (I have a 2465, and that has neither the A5 problem nor the infamous Dallas battery-backed RAM).
If the Dallas battery hasn't given up the ghost yet, you are lucky. It contains the calibration constants, and you don't want to lose those!
You will probably want to recap the main PSU board sometime.
Plenty of instructions to be found on gurgle. Many of those results are links to this forum.