Technically, this one is as well, but I am choosing to see it as the Iron Grenadier answer to the GIJOE SHARC and COBRA Sting Raider.
Behold, the Iron Angler!!!
It was a very easy custom to make. Just paint and minimal disassembly/re-assembly. I only had to remove the engines and the screws from the main body, didn't even have to take it apart.