You don't need to take the engine out to do this fix. I suggest you buy
a Haynes manual and follow it to the letter. It takes a long time change
the gasket - but its not difficult with the right tools and time!!
If its a leaking gasket - you should notice antifreeze on the right hand
(drivers side ) of the engine just below intake manifold.

We just had ours done at a local garage total cost was $780 CDN including
tax on a 1998 Chevy Malibu LS. Took them about 5 hours.

I do not know how much the actual lower gasket manifold repair cost because
I had them change the spark plugs whilst they had the upper and lower
manifold off the car (just charged for the plugs they said). The seal on the
top of oil pump drive gear was done as well (its where the distributor went
in the older cars). also an oil change and filter, new antifreeze and
gaskets for the rocker covers and ERG valve.
I considered doing the repair myself ( have the repair manual) but there is
a lot of stuff that has to come off and I am getting too old for this kind
of stuff.

It started with a slight leak of coolant  from the drivers side of the
engine, around the lower manifold gasket and it ran down the front of the
block.. There was a drip occasionally of coolant, and would quit for a
couple of months, but we have just started to have some really cold weather
and when the engine cooled off, the coolant just started to piss out of the
manifold gasket. Actually on closer inspection of the engine oil you could
see it was slightly orange colored.

The annoying thing is, this is a common problem with 1996 an up 3.1 and 3.4
litre engines, The lower manifold gasket starts to leak around 70,000 miles
(120,000 kms) GM is aware of this problem and if you are out of warranty you
are screwed, GM generally will not cover it.

I considered Bars leak or chemicals like stop leak as a temporary cure but I
felt were a bad idea because they just create bigger problems.

$780 is a lot of money for a repair like this but a new engine is going to
cost about $3000.

Hope this helps towards answering your post.

I would like to know if a leaking gasket in a chevy malibu would need to be
changed soon or can it tear up the engine as it is getting cold? Is there
another solution to taking around the engine out and what are the real
signes of a leaking gasket?