Do you ever think "pentatonics" when soloing? Guitarists live and breathe the pentatonic scales, but most pedal steel players think in terms of major scales (and minor scales) when soloing, or they solo around the chord positions.
"penta" means five, and a pentatonic scale is just a five note scale that blends very smoothly with the relative chords in a given key.
Blues (minor) Pentatonic: root b3 4 5 b7 (root)
Country (major) Pentatonic: root 2 3 5 6 (root)
The tab below shows the basic 5 note groupings in 3 positions. They are based on 3 positions of the major chord... for example, C on fret 3 w/ pedals A & B, C on fret 8, and C on fret 13 (or fret 1) using the E to Eb knee lever. The sliding riff shown is one of hundreds that uses these 5 notes.
Every major scale has a relative minor scale (same notes, different root). The C major scale and the Am scale have the same notes. The patterns and riffs shown below will work over chords in the key of C and in the key of Am. They will also work for blues and rock in the key of A because for blues you play off the minor pentatonic scale. Blues and rock solos are often the minor scale played over the major chord ( or the 7th chord ). So for Blues in the key of A use the Am pentatonic scale. For Country, play the major pentatonic scale. Major pentatonic has a sweeter and more appropriate sound for Country. So the patterns and riffs shown below will work over chord changes in the key of C and sound "country". Over songs in the key of A they will sound "bluesy". Playing along with a rhythm track is the best way to hear the different "moods" of these scales.
Here's a handy shortcut for blues and rock soloing on E9: drop back 2 frets with your bar from the "no pedals" position of the chord and press pedal B. That is the minor pentatonic scale with the root on string 7. So blues in D.... you play on fret 8 ( because D major is on fret 10 ), blues in Bb... you play on fret 4, etc. This position is shown in the beginning of the tab. Fret 3 is Am pentatonic. It is also C major pentatonic.
There are many sliding patterns that involve strings 5, 6, & 7 and pedals A & B and move from fret to fret, similar to the last riff shown below. Have fun.