Thanks for the tantalum info FireFragon, I'm from the firmware side of things, so my EE skills cause me more problems then they solve.
. . .
You did set a bit of a high standard when you replaced all the 'lytics on the main board, though, and it seems foolish of me not to do the same thing. Did you replace the main board caps with tantalums or did you use new electrolytics?
I only replaced the aluminum electrolytics. I did buy many of the tantalums, but decided to leave them alone. There really aren't that many tantalums, the problem is that the parts list does not distinguish between aluminum and tantalum and bipolar. The only way to find out is to have someone tell you or to actually look at the original parts. The latter can be difficult before removing the boards.
Some tips on removing the main board. The removal instructions give a complex process to remove the power switch assembly. Completely unnecessary. Just unscrew the screw at the front that holds in it, then you can just twist it out of the piece of connecting plastic and (holding it carefully!) remove the entire assembly in one piece. Putting it back is just as easy. Just be really, really careful with the CRT leads. They are very delicate. If you don't have a steady hand, lots of patience and plenty of small tools then I wouldn't recommend removing the main board - you really don't want to fark up the CRT!
Make sure to get lots of pictures on how things go back together - especially for the CRT leads which are in a dark hole. Also be careful replacing the capacitors under the delay line. I propped up the delay line with something to give me just enough room to work. It was still tight. There is also a wire that is held down by a retainer in the board. Mine broke! Pretty trivial, I will use a piece of Kapton tape to hold the wire down because I don't have a replacement, but hopefully forewarned is forearmed!
Here is my parts list for the main board. My scope is pre-B050000, but the parts lists does not list any changes that affect the electrolytics so my replacement list should be adequate. I purchased everything at Mouser. For a small shipment Digi-Key has slightly less shipping, but includes tax. In this case, Digi-Key either doesn't have the parts that I used or are as much as 50% higher in cost. To be fair, there are a lot of parts that Digi-Key has and Mouser does not (but not for this project).
C0102 290-0973-00 100uF 20% 25VDC UPW1V101MPD 100uF 35V 20% 105c 0.24
C0107 290-0943-02 47uF 20% 25V UHV1V470MDD 47uF 35V 20% 105c 0.212
C0114 290-0943-02 47uF 20% 25V UHV1V470MDD 47uF 35V 20% 105c 0.212
C0121 290-0943-02 47uF 20% 25V UHV1V470MDD 47uF 35V 20% 105c 0.212
C0130 290-0776-01 22uF 20% 10V UPW1E220MDD 22uF 25V 20% 105c 0.16
C0152 290-0943-02 47uF 20% 25V UHV1V470MDD 47uF 35V 20% 105c 0.212
C0185 290-0943-02 47uF 20% 25V UHV1V470MDD 47uF 35V 20% 105c 0.212
C0218 290-0943-02 47uF 20% 25V UHV1V470MDD 47uF 35V 20% 105c 0.212
C0221 290-0943-02 47uF 20% 25V UHV1V470MDD 47uF 35V 20% 105c 0.212
C0307 290-0943-02 47uF 20% 25V UHV1V470MDD 47uF 35V 20% 105c 0.212
C0325 290-0943-02 47uF 20% 25V UHV1V470MDD 47uF 35V 20% 105c 0.212
C0335 290-0943-02 47uF 20% 25V UHV1V470MDD 47uF 35V 20% 105c 0.212
C0512 290-0246-00 3.3uF 10% 15V Axial Tantalum
C0536 290-0246-00 3.3uF 10% 15V Axial Tantalum
C0723 290-0943-02 47uF 20% 25V UHV1V470MDD 47uF 35V 20% 105c 0.212
C0731 290-0944-01 220uF 20% 10V UPW1C221MPD 220uF 16V 20% 105c 0.25
C0732 290-0944-01 220uF 20% 10V UPW1C221MPD 220uF 16V 20% 105c 0.25
C0733 290-0943-02 47uF 20% 25V UHV1V470MDD 47uF 35V 20% 105c 0.212
C0738 290-0943-02 47uF 20% 25V UHV1V470MDD 47uF 35V 20% 105c 0.212
C0740 290-0943-02 47uF 20% 25V UHV1V470MDD 47uF 35V 20% 105c 0.212
C0957 290-0804-00 10uF +50-20% 25V UPW1V100MDD 10uF 35V 20% 105c 0.16
C0977 290-0246-00 3.3uF 10% 15V Axial Tantalum