I've recently bought myself a 1980 Fretless 4001 bass and find myself in need of some help on how to go about setting it up
1: The neck has too much relief and I am under the impression that adjusting these truss rods is a bit different than I might be used to. Is there a website out there which is trustworthy in showing how this process should be carried out?
Welcome to the forum! Refer to page 5 of the Owners Manual
. Refer to the bottom paragraph of the second column, where it explains how to adjust the neck of an instrument mad prior to Sept 1, 1984.
For more info, check out my website: Joey's Bass Notes
then go to Rickenbacker Bass Guitar Maintenance setiing up a 4001FL would be the same as a fretted 4001.
2: I would like to lower the strings at the bridge more so than the bridge seems to allow for - are there any non-destructive alternatives to get the strings lower?
Once you get the relief out of the neck, the action should improve. Then you can make adjustments to the bridge, if necessary.
3: The bridge pickup makes a curious fizzing sound when I play notes with it activated. It does not make any abnormal noises when I do not play, does anyone have any ideas on what this could be?
Check the condition of the contacts of you pickup selector switch and your output jack. Make sure they are not bent out of shape and don't have dirt/corrosion on them.