you need to decompile the mod and find the code you need, then transfer that code into the correct places meaning the correct methods its injecting into and edit the code until it works for you, it should show the classes its using and where you need to put the code. If youre not sure where to look, look for something like this: @Inject (method = { "methodName" }, at = { @At("HEAD") }), it will be above the methods and then find those specified methods within your client.