TA02 Parts
Some are, some aren't. The optional camber links are, shocks obviously, dogbones (not axles), you can use the front hub carriers as long as you have all the bearings, and axles as I recall. The front uprights work, pinions (obviously), miscellaneous metals (screws, ball studs) are, diffs fit very nicely (both ball and one way), outdrives, those silly hinge pins with the threads on them. That's about all I can think of off the top of my head.
Basically a mildly modified TA02 parts car will help out a TL01 quite nicely.
Since I wrote my original post, I've gone back to the stock LA rear suspension and added the 2mm HPI spacers to the rear as well (removing them from the front). The car had a tendency to push badly with the wider rear, now it tends to hook a little if I'm sloppy with the throttle. I need way more practice to be competitive with the fast guys, but it holds it's own with others in the beginners and old farts who don't practice enough class.