Bad Heater core?

I have a '95 Ranger and I just had my heater core on my truck replaced. Lucky for us that was the first year Ford decided to ditch the access panel for a quick fix. So I tried to do it myself but it was just too much, maybe with a friend and more time I could have done it all. But the whole dash has to come out as well as the A/C unit to gain access to all the bolts that hold the blower unit in. It's a bit of a show. So after getting it back together I started to shop around because being winter I needed heat like now. First quote was $850 second quote was $700, that's what I said f it and tried myself. But luckily my wife had a cousin who was a mechanic who could help and did it for significantly less. But that's pretty much what you are looking at.

One thing you can do in the meantime which is what I did because coolant was puking into the cab was to run a bybass which was bascially disconnecting the input and outlet tubes from teh fire wall that go into the heater core then find an adapter at say homodepot to connect to lines to one another so the antifreeze will still keep flowing through the system, but you won't have heat. If it was warmer you could run it as long as you wanted basically. But I suppose you could try this if you didn't mind being cold and you didn't need defrost or **** like that to see if it really is the heater core or not.

Hope this helps, btw the part is only like 40 bucks or so what a show right?!