What are the benefits and issues related to retrofiting a W124 mono valve in my W123?

Issues (That I see)
1. I believe the brackets that attach to the firewall do not match so there might be some mounting hurdles to overcome.

2. Do the electrical plugs match? I think they do?

3. I don't believe the W124 has an auxillary water pump. But that may not be an issue on a retrofit.

4. Are there be functional problems that are likely to arise?

Benefits (That I see)
1. The monovalve kit/set up for the W124 is more reliable than the W123 system. Specifically the MTC replacement for W123's.

2. Not having to waste money on MTC kits that don't work.

Conclusion: Please give me your opinion as to whether this is worth trying. I'm sure I could find a cheap W124 unit at the junkyard. I am fed up with the quality of the MTC replacement (as I know many of you are as well)

Background: One of my w123 monovalves is currently stuck open (heat overrides AC in summer), it needs a new coil. The other w123 monovalve is stuck closed (heat goes cold on highway in winter). I know why these "issues" are happening and what it takes to correct them. But I would prefer to retrofit something more reliable. Haven't decided to do the manual cock valve (another option) yet. I was hoping to stay with something more OEM.

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