electric jacks

do your self a favor and avoid happijac(Crappi Jac)they have pushed sub grade products on the rv market for years and their new improved models appear to more of the same !!!!!!!

Atwood makes electric jacks. Here is a Link.
I’m not recommending this vendor but did notice they show the mounting plate with hole pattern. Not sure what brand you are referring to but they probably also show the mounting plate with its associated hole pattern. I know my Rieco Titan mounts have multiple holes.
Regarding cost, the Rieco Titans are more expensive than Atwood. I too have a negative impression of HappiJack.

Yes they should, I retro fitted electrics to my 1990 S&S without any issues. The only thing that was semi-difficult was figuring out how I was going to run the wiring.

Rieco-Titan are same bolt pattern. I discovered few weeks ago Atwood truck camper jacks are no longer in production. Can still find some in stock but due to no longer made I'd be hesitant to recommend.
Better jack in my opinion but product line sold and Lippert discontinued.
Rieco also makes a conversion kit for some Atwoods.