1966 Factory V8 Valiant Signet Restoration For My Other Daughter

Just documenting this for future updates... the switch crumbled do to the Az heat......

Factory Switch
2587564 NOS = $400+

Potential Superseded part I ordered NOS for $98
3502126

After weeks of searching for answers about the part numbers and applications of the MOPAR Heater/AC controller, I've learned there are no definitive answers and that those who have the controller for sale, part# 2587564, believe they are holding gold in their hands. I understand the scarcity of certain parts allow for a premium price, but I thought this was supposed to be a 'hobby', not a cutthroat business. I have seen that specific part# on the interweb for $350. Of course, that's the number I need. Or is it?
So here's what I've found and here are my questions - photos included.

Mopar AC/Heater Vacuum Switch pt# 2587564 replaces and is the same as #2096084 for 1960, 1961, 1962, 1963, 1964, 1965, 1966, 1967 Models: it is the 5 button a/c and heater vacuum switch for 1960 1961 Plymouth, 1965 Plymouth Fury, 1966 1967 most Chrysler, Plymouth, Dodge vehicles, Valiant, Dart, Barracuda, Belvedere, Coronet, Satellite, Charger, GTX, R/T, Polara, Monoco, Imperial.

I've also found these part numbers which are supposed to supersede the #2587564… pt# 2096084 seems to be the most common and the first number to supersede the #2587564. Others are…

3502126
2587564
1995501
3431020
3895790
2820487
3895033
3431017

and this… Part Number: 2587564 [supercedes 2096084] Years: 1960, 1961, 1962, 1963, 1964, 1965, 1966, 1967, 1968

and this… Plymouth 1968-74 New MoPAR A/C Heater Vacuum Switch 3502126 repl 3431020. If you're not totally confused by now this may do it. #3502126 that fits '68 to '74 supersedes #2587564 which fits '60 to '67.
I've also looked at '66/'67 wiring diagrams and '68/74' wiring diagrams and noticed the wiring for these switches are pretty much the same. BUT look at the 3 pin connectors (see the photos). On the #2587564 the 2 pin is connected (like a jumper) where on all the other switches the 2 pins are separated.
Therefore, here is the question. Are these switches interchangeable? If so, you will be able to replace your '66/'67 switch for a fraction of the cost. The later '68 to '74 switch can be had for $50 not $400 for the #2587564.


Price gouging OR fair price?