jacking

You mean aside from a 4 post lift? 1-1/2 ton floor jack under the front cross member and safety stands under the jack points behind the front wheels. The back is bigger problem but you can make a jack adapter to jack from the rear spring perch on the rearend. Otherwise, jack points in front of the back wheel and safety stands on the lower shock loop.  If you make the extension to get up to the spring perch, you want it welded good and strong because that extra length wants to roll over real bad. I used some channel around the spring with 2" pipe spacer and 1" bolt to the jack head.... until I got my lift 

Most floor jacks are too tall to roll under any lift-points on a C4. Or destroys the front spoiler trying to get the jack under the front cross-member.   I have 3 jacks and none of them roll under the 85. So most cleaning and maintenance operations are performed on my backyard 4-post lift.

But I have found a way to get the floor-jack under the lift-points. I drive the car up onto a 12" block of 2X4 placed under the tires I want to lift. Like both fronts, or both on one side. Works great when you have to get a wheel off.

You have to be "smarter than the problem" to solve it.

Buy a 3 ton, low profile racing jack. 

Harbor Freight has tons of them.

As DaveP suggested, driving the front onto 2 x 8's stacked two high does the trick for us. Then a single floor jack under the main cross member will get it done. I put a piece of 2 x 8 betwwen the jack pad and the cross member to spread out the force so I don't dent up the metal. Front jack stands can be put under the main frame just behind the front wheel wells. the frame curves in towards the motor and there's a flat triangular pocket the works great to locat the jack stand top pad.

If you find a copy of "Corvette Enthusiast" from August of 2010 there is a great article on how to jack C4.

The FSM shows the jacking points. My 2 ton jack doesn't have a problem handling the job, especially since the '99 T/A wheels lower my 'vette even more.