Manager Carl Jarrett was delighted with his new signings, saying: "Josh is a player I have had my eye on for a couple of seasons. He's going to be a top player at this level and will be a great signing for us. He's young, wants to learn and push on and I'm very happy to get him signed."
Carling is well-known to Marske fans having spent just over a year at the club between 2012 and 2013 before moving over the hills to Guisborough. He spent three seasons at the KGV before spending last season with Bishop Auckland.
Jarrett said: "Leon is a very experienced player at this level and will be a very good signing. He's done well for everyone he's played for, he's very dominant in the air and has also captained a few teams so his leadership will be vital."
Both players are set to play a crucial role in what is set to be a very exciting season in the Northern League, with re-structuring of the pyramid and adjustment of ground gradings meaning the league champions are guaranteed promotion to Step 4.