After his record deal with Mountain Management expired, Glen was now a free agent to perform with other acts properly and it was around 1980 he was introduced to German rock guitarist Michael Schenker who shot to fame in Scorpions and UFO respectively.

Shortly after leaving MSG, Glen formed his first band GMT which consisted of Vocalist Robin McAuley, ex Motorhead drummer Phil 'Philthy' Taylor, and Thin Lizzy guitarist Brian Robertson.

This then changed when Ronnie and Alan were unable to do a handful of shows so Ted brought in Glen on bass and SAHB keyboardist Hugh McKenna.

This line-up of SAHB disbanded in 1995, before reforming in 2002 for a tribute night to Frankie Miller at The Barrowlands in Glasgow with ex Nazareth guitarist Billy Rankin on vocals.

The band performed numerous tours and festivals across the UK, Europe, and Australia before once again disbanding in 2008 after the departure of Zal Cleminson on guitar.

The band carried out a handful of shows that were pre-booked with guitarist Julian Hutson Saxby but after that, they decided to move on to separate projects.

This project consisted of material that Glen had been playing throughout his career from SAHB, Michael Schenker and Ian Gillan.

Glen and Ted McKenna worked with Australian guitarist Gwyn Ashton, on an album called Prohibition in 2004 and performed shows to promote it.

Later in 2004, McKenna was working with Paul Rose and asked Glen to come in for some shows with the band but shortly left and was replaced by Alan Thomson.

He is a member of the reformed 1970s band Cafe Jacques with drummer Davie Halley, keyboardist Stuart Clyde, and original vocalist/guitarist Chris Thomson.

The band released a 3-track EP called Lifer before disbanding following the death of drummer Davie Halley.

Slade was a member of AC/DC as well as worked with David Gilmour, Manfred Mann, The Firm with Jimmy Page, Tom Jones and many more.

In and around 2018, Glen decided it was time to put all his stories and his experiences on paper so he collaborated with author and former SAHB Manager Martin Keilty to write a book called The Bass Business which received reasonable success and sales.

Lead guitarist Peter Higgins has taken the reins of the project and in 2022 the band recorded their first EP and are currently working on a debut studio album yet to be named.

Due to health related issues, Glen is no longer able to tour extensively as he is currently awaiting surgery on his knees.