Yes, as I recall, it's a real PITA to get at those caps. I think your option to add parallel caps may be best, if there's room to fit them and the extra wiring in there. If the old caps haven't already leaked, but are electrically open or high-Z, then I doubt they ever will leak - the guts are essentially disconnected from the outside world. They usually fail due to chemical disintegration of the tabs that connect the capacitor slug to the can or the terminal lugs. The actual cap element is often still like new inside, but disconnected.
Ed
