First, kudos on appreciating stock.
Next, your 'mechanic' apparently has little wisdom when it comes to Clevelands. Unless he is basing his thoughts on some other parameters which you didn't share with us ....
the Holley and Offy are fine.
BUT, original is not a Holley and Offy. What do you really want?
The Autolite has a dubious reputation, but some owners are still running them with acceptable results.
This is Pantera Land.
The choice is yours.
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