Last night I found a couple of 2 1/2-inch tubes from an old treadmill, which I thought might work to nest inside my frame rails to extend them for working front jack points. Today I set about getting the axles and bearings out of them. Spent two hours.
This old treadmill was built right. The bearings are beefy and they’re carried by some kind of super-tough plastic that’s pressed in. I was able to drive the steel axles out easily with a five pound sledge and a drift, but the bearings and their carriers would not budge with any kind of persuasion I could muster.
I tried drilling around the bearing and broke two bits in the plastic!
Finally I hit on using a hole saw. Luckily I had one the right size to fit over the bearing and still fit in the tube.
With the bearings out it was down to cutting/prying on those stubborn plastic inserts. 
Vice grip and muscle finally freed them.
Tubes are actually different diameters. The one pictured is more like 1/8-inch wall. I slipped it into a piece of 2 1/2-inch exhaust pipe and now it’s about the same diameter as the other, heavier pipe.
They should both hold the car up; the heavy, 1/4-inch walled piece is going to be harder to work with. I’ll just put that one on the passenger side to get the corner weights closer to even. 
Next order of business is cutting out the frunk floor and test-fitting these in the frame tubes. I’m going to have to angle them slightly upwards to fit inside the frunk, and I’ll probably also have to cut, pinch and weld these tubes as well, tapering them to the front and adding a flat purchase to weld the actual jack points to.
I may also add some kind of heavy-duty threaded flanges toward the back of them, with the idea of creating a bolt-on “beam” to attach a normal VW tow bar.
Along Came A Spyder 