I don't have the Santucci book, but I can tell you that GM used the separate-coil arrangement in both the cars and trucks from the first electronic years on 6-cyl's up until they went with the integral head. The most common applications that you will find these in were Novas and the Buick/Olds/Pontiac clones. One of those is a very good possibility for your donor vehicle.
There is no real difference in reliability between the two systems. GM went with the new configuration most likely due to the lower cost of using bent8-compatible parts. Let's face it, if the only top-of-the-distributor piece they had to change from a 6 to an 8 was the cap, it's cheaper for inventory.
In '78 they went with the integral head and all sorts of "corporate" engines and components, did away with the big-block Buick and Poncho motors and painted everything blue! What a sad time.....
Oh well, enough whining about the past. Give a holler if you have any more questions.
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David
