Murray (pictured), 36, was assistant to Cox when he was manager at Mansfield Town.
More recently he was manager at National League North outfit Boston United, where he had been since last year, after managing Mansfield from 2014-2016 following Cox’s departure.
As a player, Murray was a midfielder starting out with Derby County and playing 54 games for them before moving on to play for Mansfield Town, Kidderminster Harriers, Notts County, Burton Albion, Carlisle United, Torquay United, Oxford United, Luton Town and Mansfield, for whom he made a total of 142 appearances in two spells.
Marvin has worked with Cox at Barrow, Torquay and Mansfield as both a coach and an analyst.
Danylyszyn has previously worked alongside Cox as a coach with the youth teams at Mansfield.