K Line Blackjack GG 1 tire replacement

Slip it between the wheel and side frame, there is a gap. Fish it over the top of the wheel with a dental pick, or popsicle stick trimmed to a hook, shish kabob skewer, Allen wrench, crochet hook, etc. then stretch it over the wheel.

Remove the pantograph(s) first so you can use both hands if you must. Just one if you are ok with a tables edge, etc.

They clip on a grooved body post (pic 2).

Held only by the post/spring (top of pic 3) in the grooved body post. A firm pry at the center of the frame will pop them off. A firm tilt/press/wiggle ususlly reseats pretty easy. Watch the plastic at the 4 corners, they are nearly just sandwiched in there; some fall out. Pretty easy to slip them in after the pant. is mounted if they come loose.

You should try to give all the info you have for questions like this. I am just assuming it is a PostWar size. Mine is PW & Tuscan, not black, but I think it is the same  loco (Minus some dirt & dust  the line on this tire is track gunk. You can see my fingernail scratched some away at 7oclock point)

A scale sized one would likely be very different. 

Edit #2 & #3  they got inverted. Updates have this device messed up again. Weekends are awful for that.

it is semi scale size 

thanks ,I will give it a try

Bill