Of bushings and bearings

Hi,
There was a thread on here a while back on the merits of bushings vs
bearings.
I had no reason to doubt what was said but here is my particular example and
questions:

I have a Giant XCX frame with the standard four ball bearing pivots and
Nylon bushings elsewhere (ignoring shock pivots).
The rear end eventualy became too sloppy after around 3000 km of pure
off-road all weather riding and intermittent regreasings of the bushings.

What I've noticed is that while the bushings are worn beyond their service
limit the bearings still run reasonably well. The bearings are a bit notchy
but they have less slop.
On top of this I just found out the bushings are 8 x $15AUD to replace where
I can get bearings for a small fraction of that cost, they're easier to
replace and maintenance free.

I'm possibly going to replace my frame, it's very beat up and the air shock
leaks, but even so there's no point chucking the old one in the bin if it
can be made servicable.

Has anyone heard of:
Aftermarket bushings for giants?
DIY bushings from existing nylon parts? ie. cylinders + washers?
Machining custom bushings?
Machining frame to take bearings?

And one more thing, my motorbike swingarm uses needle bearings in the rear
suspension, do any MTBs use them?

In ,
Duncan typed:
snip

And one more thing, my motorbike swingarm uses needle bearings in the
rear suspension, do any MTBs use them?

I had a GT LTS-1 that used nylon bushings. The bike was constantly
squeaking like a old bed. I upgraded to Turcite bushings which lasted
longer. I didn't lube them as I believed this would only attract dirt and
speed up the wear. These lasted longer. I eventually added the needle
bearing upgrade kit. It stiffened up the rear of the bike considerably and
no more squeaks ever. I eventually sold the bike to a friend of a friend,
and it is still going.

I wish more suspension designs used needle bearings. I think they are much
better suited to the job. The ball bearings on my Bullit wore out after
only 3 months of wet riding.

Mike