is it possible for water to leak from the timmig cover? how hard is it to replace the gasket? its a el v8

Yes it's possible, but unlikely. Most leaks happen from the thermostat housing to intake manifold gasket and from the waterpump and thermostat housing to rubber hose connections.

Replacing a t/c gasket in place in a car is a painful job. Radiator, fan, shroud and hoses should come out, waterpump off, balancer removed, gently lower sump at front, completely remove front 2 sump bolts (from both sides of the sump, total of 4 bolts). Remove remaining t/c bolts. Gently pry t/c off (there are 2 dowels holding/aligning it). Replace gasket and everything above you had to remove.

Since you're in there, replace the balancer seal, waterpump and the short 90 degree rubber hose. Check thermostat housing 5/8" OD thermostat bypass pipe for corrosion, replace if it's dodgy. Check t/c for corrosion, replace if pitted.

the windsor timing covers are a problem when they havent been run with coolant/inhibitor. they corrode in the water gallerys that lead to the waterpump., common failure. genuine ones are around $350, i have replaced a couple of timing covers from this.

i fixed my leaking timing cover a couple of months back now, the gasket had progresivly been getting worse on the l/h gallery. Not to bad a job if you have a three legged bolt on puller, just pull the thermos off and theres enough room (i pulled the whole radiator out and didnt need all that room) get a 5/16 unf tap to clean the threads on the balancer and loosen the bolt that holds it on but leave it in to push on so you dont damage the threads on the crank. i got mine all sorted in a bit over half a day so its a pretty easy job, i also put a new water pump in (for $80 it was silly not to)

Its not a hard job you have to be a bit carefull with the long bolts that hold the timing cover to the block, sometimes they seize in the alloy cover and you can snap them off, then you have a problem. The last one i done we snaped 2 bolts.

the mechanic snapped the right hand bolt on mine and used some cement putty to fix when he changed the water pump. Dreading the day we have to tap a new thread