I have replaced mine also...1983 F 150...using the remove the glove box trick. The part was cheap and the work went ok.

Now...just in case any feel this is expensive...an acquaintenance recently made the decision to junk a 1990 Ford Festiva because of a bad heater core....virtually impossible to get at and the tiny replacement core was priced at $145!

There's a lot more to economy than the cost of gasoline....keep those old trucks on the road (I am smiling now....just fixed my clutch linkage for $23).

 

does n e 1 know if the 2001 f150 heater core is changed as the same way as the 86's??

thanks