The mounting holes aren't part of the block, though mine is 52mm as well as string spacing of 52mm. And the three baseplate holes are the standard Fender arrangement. I won't be using a tremolo cover. Because it needs to be short, the string holes should have just enough countersinking (?) to swallow the ball ends, but not way up inside like on some blocks, because that's obviously the length of string that provides the leverage. I think recessing the springs would be more work than is needed, but if the block could be about 1 3/8 = 35mm at the end of all processes, it'll work. I'm going to set it to a slight float, but for all intents the block pulls up (shorter) into the body. I bought this Japanese "Jagmaster" body cheap off of Ebay, made between 1996 and 1998. It's pretty clear that Fender uses the Japanese market to test-drive configurations before springing them on America, because now there are all sort of double-humbucking Jaguars and Jazzmasters in Fender's line up.
I just got my shipping notice for the neck today :hello2: so it'll start moving along, though I have to scallop the neck myself - I'm getting a Warhead 24.75" scale, 24-fret neck, which "converts" to the Jaguar body too. I'm getting good vibes.... I posted up some trade bait here:
http://www.unofficialwarmoth.com/index.php?topic=18565.0
But I could understand if you need money, instead. There is no big rush though, the scalloping may take me a while, so you could probably run the block mixed in with your other experiments.