Hey Bird, I hate to be the one to break this, but if you expect the new hull top to bolt right on you have a surprise in store. Now, if you plan to make it a lift off top it's no problem, but as jagman said, they have changed the screw hole positions and the early versions are no longer available. I looked everywhere for a lower hull like yours, with just one screw at the front, and no joy. I have a brand new lower hull that would bolt right up to the upper you just ordered, but international shipping rates prevent me from just sending it to you. So once you get the new upper, the only way I can see to make it work is to go with a lift off top, and that means you'll need lower hull bracing. You said you're not afraid to get your hands dirty, and that's a good thing because you do have some work to do. It will be fun, though, and you'll get a great sense of accomplishment when it's done and we all tell you how good it looks.
We'll all be here to help so if you need any videos or dimensions from any of my tigers or anything like that, just sing out and I'll hook ya up.
Now, as for the RC5HL, I tried one and didn't like it. For some people they work great right out of the box but I wasn't one of those guys. I sent mine back for a refund and bought an IBBU2.

If I were you I'd spend the extra money and get the Clark TK22. It will run fine on your TX and you even have a five channel so if one channel can be assigned to a pot you can later add a Viper to get volume control from the TX.
What do you plan to do with the Pan Tiger upper hull? That might make a great bunker diorama. I've seen photos of tank turrets mounted on fixed pill boxes along the beach. Pretty cool. If you get really ambitious you could even make it functional.
Keep us posted, I'm looking forward to seeing this thing come together.
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