Tower Madness, Endurance, Wave 126/327.

I’ve finally recovered from a terrible stomach virus that incapacitated me for roughly 3 days. While I was bedridden, I played a couple rounds of Tower Madness on the iPhone, on the Endurance level. This is by far the most challenging board, and I’ve yet to beat it. I’ve managed to reach wave 126 (out of 327). Anyone have tips on how to get further?