I decided to try re-checking the Hot Rod Strat with the Gotoh Floyd loosely placed in the body rout with the new bridge posts in place, this time using my steel ruler, it looks like there's going to be about 2mm clearance for the string-locking saddle screws to adjust back, I never should have trusted my tape measure....*rolls eyes*.

Okay so there's really only one issue with the Gotoh Floyd Rose bridge, the 40mm brass sustain block is a bit too long, the body really needs to be about 10mm thicker to accommodate it to allow enough string-height adjustment for a low enough action without the sustain block hitting the plastic trem-spring cavity cover when doing pull-ups on the whammy bar, dive-bombs are okay though, I wonder if Realtone Music stock shorter sustain blocks for Gotoh Floyds, I'll have to go and see if they do.

There's another issue which has to do with the threaded mounting-screw holes in the new locking nut, they don't line up with the holes I drilled in the nut-shelf at the headstock end of the neck, I might need to buy a new neck for the Hot Rod Strat to sort it out.