Ok that's actually pretty awesome. Guaranteed not to break. Nice!
Well, i'll send this piece o crap back first and figure out what to do. Any other suggestions for one?

If I can do this, you can do this. Where did you buy the replacement from? Rovahfarm or ebay? Send the piece of junk back and buy another NEW one off of ebay or from Rovahfarm. I've purchased from both and have never had an issue with product. I think Atlantic British sells them too.

Radiator Coolant Overflow Reservoir Bottle Tank for Land Rover | eBay

OK. Ive received the new resevoir and have a break before the rain/snow arrives. Now I need to swap it out. Question. Is this as easy as loosening/detaching the two hoses, taking out old resevoir and dropping in the new one? The fluid that comes out of the tank when removing the two hoses, will i need to refil the tank. Sorry guys but ive only done repairs involving metal (brake pads, window regulator, etc) and no fluids.

Where is the thermostat?

Thermostat is on the block, front of the engine. Follow the top radiator hose to the engine from the radiator and you'll arrive at the thermostat housing.

once you replace the expansion tank, you'll need to refill the cooling system and bleed it. It's pretty easy on a d1 and the amount of bleeding required will depend on whether you pull another hose to replace the thermostat while you have the expansion tank off or not.

if you're going to replace the stat, make sure your kit you order includes the gasket. (Learned this the hard way!)

10-4. Gasket. Check.
Thanks

The broken one was from ebay. The new one from rovahfarm. Got a brass plug while i was at it. Now i need to get a tstat and just do it and the tank all at once.

You really need to read the service manual - Rave. We have a link to it in the tech section. It saves having to ask so many questions to get the simple things done. It's written in plain language, very easy to follow. Fleabay is not my number one choice for Rover parts, never has nor never will be.