Hmmm... I thought that Jagdpanther looked familiar
Thanks for putting this up Matthew.

Kevin, I've used the same 1/76 Revell kit for the Jagdpanther shown above. It was my entry for the first Matchbox Campaign here in Armorama.
I doubt if there were any AM tracks for this (I guess for any of the 1/76 Matchbox kits as well???), so your best bet is to make do with the kit's tracks and improve its looks by putting on a sag. I've used stretched sprue to weigh the track down. I drilled small holes on the hull sides for the sprues and fixed them with glue. Additional hold was provided by putting small drops of super glue between track and wheel.

Fortunately, the Jagdpanther doesn't need much sag so it shouldn't entail much work:

You may use pins, wire, to weigh down the tracks. Other folks I heard just use super glue. Try and see what works for you. Here's another 1/76 Matchbox kit -- the T34. Same process, though I've used staple wire in this case:

GAP: Sadly there's not much one can do with the gap where the track ends meet. Well, you can probably try and fill it up. In my case I just let it be -- anyways, the base provided in the kit can be useful in hiding it.
PAINTING: I'd go with Alexander's advice. Paint the tracks when its already mounted. I prime it, and try not touching it as much when its already painted. Best if you can get hold of Future -- I use it as further protection against flaking. Here's more info you may want to read on:
http://www.swannysmodels.com/TheCompleteFuture.htmlHope these help. Good luck on your project!
Cheers,
Tat