Chris,
balancers are quite easy but if you are using the Explorer front cover you need to sort out which water pump you can use.
The Standard Explorer pump is reverse rotation and won't work with V-belts. Also the depth of the pump is differant, shorter by about 1 3/4 over the normal v-belt pumps. Ford still does their Hot Rod pump for V-belts, the same depth as the Explorer pump, but no longer do the V-belt pullies to go with it. Also, it doesn't fit the Explorer type front cover. Early front covers are readily available now and cheap, about $60, so might be an idea to change that if you need to change the pump.
Back to the question and dampers, being 3,000 miles from Detroit we take the easy option and go for a universal damper like the Professional Products 80007 ( 50oz ) or SFI 90007, they come as the shortest option and are drilled for three and four bolt pullies. If the spacing isn't right use one of their spacers, 81006 ( .350 ), 81007 (.950 ) or 81008 ( .875 ) to get things aligned. They are cheap, about $12 each, so we always have a selection to make life easier.
In my experience the RCR air-con brackets etc are set up for the shortest option, ie no spacers, but you need to resolve the water pump issue first.
For a bolt on v-pulley have a look at the March range, they do all sorts of combos for differant spacing, diameters etc. We normally order the shortest and jugle things with the damper spacers if needs be.
Mike
Actually, just double checked and it looks like the '94 Explorer front cover will take a conventional pump or the Hot Rod pump so you had better check. The short Explorer pumps didn't come out 'till '96, maybe someone more up to speed can confirm.