How do I make a clickable signs set a block?

I made a command where there is a clickable sign that teleports a player to spawn. Here is the command:

/setblock ~ ~1 ~ minecraft:wall_sign 2 replace {Text1:"{text:\"Start\",clickEvent:{action:run_command,value:\"/tp @p[c=1] -658 104 -690\"}}"} 

How do I alter the command to setblock a redstone block?

I tried this:

/setblock ~ ~1 ~ minecraft:wall_sign 2 replace {Text1:"{\"text\":\"Set Gamemodes\",\"clickEvent\":{\"action\":\"run_command\",\"value\":\"/setblock -44 110 248 152 delete\"}}"} 

but it didn't work. What am I doing wrong?