You better check the tech data for the M88 version you want (armor, speed, etc.). Give it class "tank transporter" or some unattributed truck class if you want it to be a separate class (if so remember to create a corresponding formation so you can buy it!).
You also have one or two icons for unarmed AEV/ARV (see #657 for one) that can serve as interim for your M-88.
Considering M60 blade, you're right, there doesn't seem to be one in the game at all. If you're sure there should be one, you can easily edit this icon by plugging a spare blade from another blade tank into a casual M60 body icon!
Oh, and, of course it will work. If there are no ARV in the game, it is mainly (from my information) because field repairs are pointless in a game's timeframe, and it is a big way to get cheap and tough APCs and overall easy transporter... A cheat, you may say
