I wouldn't worry to much about the tick...When I was 6 my Uncle told me that engines that tick are no good....242,000 Miles later, she just ticks proudly down the road!

 

the tick could be a bent push rod as well, My 94 did that before and when I replaced the head gasket I found 4 of my push rods were bent. I replaced my push rods and cleaned my lifters and everything is ok. Now it has the normal tick

 

My xj ticks and it is the solenoid for the EGR system. On my xj it is on the passenger side near the firewall. It doesnt tick consistently, some days don't hear it at all but when it does it sounds like a stuck lifter or something. My friend has a 2001 wrangler and his rarely does it, Mostly when it is really cold outside. You can put your hand on it and feel it clicking. It is about the size of a small soup can and has a wire connector and a few vacuum hoses on it .

 

I will check that canister out , thanks