[DeTomaso] Tach adapter with ready-to-run MSD distributor?

[Mikael]

Sometimes ignition boxes have a separate wire for the tach, that wire won't work with our old tachs. That we know. But instead of buying an adaptor, sometimes you can just use the wire to the neg part of coil and ignore separate wire... depends on which brand box you have, worked for me recently when installing ICE on the Longchamp

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  Original Message  
From: MikeLDrew at aol.com
Sent: fredag den 21. marts 2014 17.09
To: detomaso at POCA.com
Subject: [DeTomaso] Tach adapter with ready-to-run MSD distributor?

Hi guys,

I am trying to help a friend who just fitted a new distributor and lost 
tach function as an incidental result.

I know that with a conventional MSD ignition system (with external box), 
you must fit a tach adapter to get the tach to work:

http://www.summitracing.com/parts/msd-8920/overview/

However, he installed a 'ready to run' distributor:

http://www.summitracing.com/parts/msd-8350/overview/

Do these, also, require the tach adapter?

Mike