You can do a heater core bypass, and leave the heater core unused in the dash.  The AC can be removed from the engine if you desire, or leave it and disconnect the belt that is hooked up to the AC.

However, if you are doing this because you want to reduce weight, sigh, then you will need to physically remove it.  The heater core doesn't weigh much, but the AC compressor unit has some heft to it...so it's your call.  Ask yourself what is your objective here. The heater cores are not that expensive, as they could be had for about $50 bucks. The AC is the costlier item due to the Freon issue, and multiple parts at play (evap core, compressor, etc.). Ford did make a service manual for Pinto's AC system so it may be worth an investment to locate one on Ebay.

When you do a bypass, you will need to make sure the bypass hose is not crimped as it will be at a weird angle. Here's a picture of such a crimped hose...there is enough opening not to impede the antifreeze passage. This picture was taken of my Pinto when I first purchased it from Florida. They did not want to replace the leaking heater core, as the previous owner lived in Florida.

I wanted the heater as it does get chilly here in Ohio, so I located a heater core. I haven't tackled that project yet, as I wanted to finish the other items first. I will let you know once I start that.

Happy Motoring!
Dan

If you are wanting to remove the unit for repair or just to get rid of it, the answer to your question is yes, it will come out without removing the dash.

If its like my 78, you need to seperate the "box" that houses the blower motor from the main unit while still in the car. It wont come out as a complete unit.