Can’t say but try “bottlenecking” or using a piece of steel pipe on your fingering hand to slide up and down over the frets.

The “Bottleneck” technique is used by many artists, usually with an open chord tuning. Eric Sardinas is one artist who comes to mind.
“Bottleneck” slides are available in any store that sells guitars and accessories. Most artists I have seen use the bottleneck on the ring finger or pinky.

I have seen the volume swells controlled sometimes with the actual volume control on the guitar. I have also seen volume pedals used, very much like an actual lap steel.

Another one to see is Junior Brown.

http://en.m.wikipedia.org/wiki/B-Bender
My dad loved the Byrds.
They had a guitar player (Clarence White) who invented a b string bender attached the strap button.
Fender marketed it. Now they are all over the place.

@josie Your dad had great taste in music. (See Sweetheart of the Rodeo.)