The simplest solution is to program the FSX keyboard shortcut for "drop all tanks" yourself. It is blank in FSX by default.
Go into the settings menu in FSX, then to Controls. Scroll down to the "drop tank" options:
Double click on the drop tank item you want to assign a key combination to. I chose "drop tanks (release all)" which opened this box:
Since Shift+D is a standard shortcut for releasing droptanks, I pressed those two keys simultaneously:
Press OK to save. Once you return to the P-51H cockpit, try the shortcut. The switches should animate and cause the tanks to disappear. (It worked for me at least.
It's not as good a solution as having the clickable hot spot in the VC, but it is far better than stopping the sim and switching to the combat model.
_________________I like Thunderbolts!
(Link to MySpace tribute page)120th Fighter Wing, Montana Air National Guard