I adjusted the suspension springs for the floating chassis so the turntable top surface is about 2mm higher than the deck cover plate. That is per the service manual. However, you must try and set the distance between the tonearm/detector arm top surfaces and the platter top surface to 19.5mm. That 19.5mm setting would be more crucial to the sound as it affects how the cartridge will meet the vinyl record. The 2mm platter height to the deck cover plate is for the ideal spring suspension position so that is what I try to set on my BG8002 decks. With the 8002 adjusted to factory settings, any surface noise you hear will most likely come from the vinyl record. Remember, there are a lot of variations with the vinyl record media. Vinyl records come in different thicknesses, the center holes are not always perfectly centered and there is often a little warping with the disk. Those are things you just have to live with. All you can really do is adjust the turntable to the ideal specifications set in the service manual.
I have a few warped records and while they definitely produce some noticeable surface noise on the lead in, the 8002 manages to play them quite well (even at 1 gram tracking force). I try not to play or keep many warped records though as they put a lot of extra strain on the cartridge suspension.
-sonavor