Hello Repair-man and JWWebster!
Thank you for responding to my post. I'm sorry I wasn't a little more clear in my description.
The thermostat picture in my first post is the 4-wire that I bought to replace the 4-wire that didn't work on Regular setting. It was not sold as a Maytag replacement part - just a thermostat with the same 4-wire config & heat range as faulty one. There are 4 wires that need connecting in that corner of my dryer - two from the heating element - a purple one that goes to the timer and a green one that goes to the thermostat on the blower outlet. A 3-wire wouldn't work there, nor would a 2-wire.
The thermostat on the blower outlet is a 2-wire and is the original - never replaced in the twenty years since I got this dryer from my parents. It is labeled 3-03035 (see picture in this post).
I do note that my blower outlet thermostat has tabs labeled Pur-Gr and Black and the only two wires in that neighborhood are green - maybe the 2-76 indicates a mid-70s date and possible replacement.
I am wondering if I have a model that was unique to Canada - hard to get any info from that era now that Whirlpool has taken over. The "H" in my model number (HDE406) may indicate a difference in the configurations. It would sure be handy to have my long-mislaid schematic. All my local experts have retired!
I guess the biggest question that I have is this: at the hi-limit (4-wire) location (see photo in my first post) does it matter where the green and purple wires attach? Obviously, the two leads from the element attach on one side but I'm wondering if the purple & green are interchangeable on the other side of the thermostat? Kind of like a no-harm-done thing - if it doesn't work just switch them. Just didn't want to ruin my new $40 investment!
Thanks for your help!