Moosens -great story on htr core replacement. I read the entire progression leading up to your working on it and it was great.
I have 87 gl wagon at 170k and will do same thing and had a couple questions - I figured i'll replace dash lights while the thing is partially removed - do you know where the specs for these are or am i just too lazy to find them?I'm a little lazy right now too,but I'd say those tiny light specs are in the owner's manual somewhere.If you don't find them soon I'll check a service manual for you later in the week.
Also - temp control slider got stuck with ice (yes ice) 10 years ago and the wife forced the slider to work - so for 10 years the silder know has about 1/4" of tangential play in it - any guess as to what it might be or what I should be ready for to try to fix it?I'm guessing the heater cock on the end of that lever/cable is the real culprit.Try to score a cock with the core,worth it if you want another 5+ years of heat out of it.
And - last question - anything else you can think of to PM in the dash while its backside is hanging out?I think you've got the right idea changing the bulbs.Orange in the ashtray is so cool.Oh,check you fan,particularly the resistor pack.Night want a new res. pk. too....clean out the ducts,re-foam the perimeters of the flaps,etc....ok,maybe there are a couple of things you can do...
Make sure the A/C unit looks good,maybe blow out the fins,or vacuum.
I did the cleaning and foam,did the resistor pack previously,but when I got it all back together the fan was suddenly shot.But,that's one item you can get to w/o the dash out.
thanks a million for trailblazing 

...you're welcome,but I'm just the first(?)guy who wrote it out nicely.
The EA81's can be yanked from the driver's side w/o removing the dash,BUT you need a Dremel type tool to cut the box.Save the cut piece and glue it back on after."clantieri" did an ecxellent job of this in his,and my,former 84 4WD wagon.