Replacing a thermostat can be messy (antifreeze spilling all over) but it's not very difficult. Follow the lower radiator hose to the engine, that's the thermostat housing. Don't know '93, but on my '98 the wrench positions are -um- kinda awkward... You can buy a thermostat at AutoXoned, but for the couple extra bucks you may as well get a better one from the dealer.

Clean up all the spilled antifreeze because it apparantly tastes good to animals but it's poisonous. This also makes a really good excuse to drain all the coolant & make it fresh.

The exhaust 'B-pipe' goes from roughly under the shift lever, back to roughly the rear axle. It's a little more difficult than the thermostat, since it's probably rusted & you're gonna break the bolts off. Plan on buying all new nuts & bolts & gaskets & rubber hangers, since that stuff is not worth saving.

If you don't have a way to lift the car, & good solid jack-stands, don't do this. When the car falls down the blood makes a big mess on the garage floor.

just for grins...
'A-pipe' is the downpipe from manifold to roughly firewall.
Catalytic converter is the next section.
'B-pipe' is next, it includes the small front muffler.
'Muffler' is what Honda calls the last section, which includes some piping from the axle back.