No, there were, back in the '80s GM Perfomance books put out that had recipes and proven methods to increase the power of some of the GM engines, all the way from the 1.8L OHV, to the BBCs. the 660 was included in the 1987 release. In fact the 660 was what was pictured on the front cover, with a Potter fuel injection manifold adorning the top.
I'm not sure you understand what Megasquirt is....
To use the Megasquirt ECU, would replace the entire OEM ECM in the case of these trucks.
I prefer Delco ECMs, since they seem to be more robust, I've only had 1 true ECM failure in about 15 or 17 years or driving and modifying my own GMs. The Delco ECM, especially when you choose a later OBD1 ECM does a lot more and is more capable IMO than any MS to date.
I have looked at MS a number of times, to see if I could use it for any of my projects and so far, other than the MicroSquirt in fuel control only mode on my bike, I haven't found a use, and even then I might try to use a '7747 to run fuel only. Though I have seen ways to possibly control spark on teh bike engine too, by using the Delco ECM.
I did look at the Commander 950 ECU a number of years ago, but never pulled the trigger and bought one, I got into tuning the Delco ECM and haven't looked back.
'Bu: The daily driver
Tha toy: 1973 Datsun 240z 12.71 @115
Old set-up: 1985 GMC Jimmy. 3.2L Turbocharged/Intercooled hybrid. 13.873 @ 99.08
Currently being reconstructed.
"If you're not living on the edge, You're taking up too much space."