I can only find shitty versions of this tab on the net. This is how it is played.
Intro
Hold down the notes on the D string while hitting the open A
G------------------------------------------------------------------|
D----------7------5-------7-----5----------------------------------|
A-----0-0-----0-0-----0-0---0-0---0-0-5-6-7------------------------|
E------------------------------------------------------------------|
[ Tab from: https://www.guitartabs.cc/tabs/m/motorhead/watcher_btab.html ]
Verse 1
Lemmy plays Open A over vocals- listen to the song
G----------------------5--------------------------------------|
D------777-5-555-5h6h7---7-5-5h7p5----------------------------|
A--0-0-----------------------------7--------------------------|
E-------------------------------------------------------------|
Verse 2
Variation on the first verse riff, just two and a half steps up.
Open D
G--------------------------------10---------------------------|
D-0-0--121212-10-101010-10h11h12----12-10-10h12p10------------|
A--------------------------------------------------12---------|
E-------------------------------------------------------------|
Solo backing
Root notes of what the guitar plays
G----------------------------------|
D----------------------------------|
A----------------------------------|
E-5-5555553-3333331-1111113-333333-|