Upgrading coupled Ember & Laravel projects (same folder)

I am currently working on a project which is using old software for the front-end and back-end frameworks.

Front-end: Ember 1.8 and back-end: Laravel 4.2.

Ember needs to be 2.5 and Laravel needs to be 5.2.

I have seen Laravelshift website for upgrading the back end which I would prefer to use due to saving time.

Now the web application is setup with Laravel and ember within the same directory.. the ember folders reside in a directory called 'client' and the Laravel files are residing under 'app'.

I have tried to upgrade Ember without completely de-coupling the projects and failed numerous times, getting errors in the terminal complaining about parsing json files - (referring to package.json / bower.json).

What is the proper way this is done? Do you have to search each dependency individually on Github and see if its compatible with the newer Ember version and install it manually?

Up till now I have used: http://ift.tt/1nQpekV and a couple of other guides and haven't made any progress.

I am using gulp as a task runner, when I run it to compile the project it spits out this error:

/Users/JCharnock/Desktop/newatp/pt2/build/js-common.js:27
var emberBuild = path.resolve(pkg.browser.ember);
                                         ^

TypeError: Cannot read property 'ember' of undefined
    at Object.<anonymous> (/Users/JCharnock/Desktop/newatp/pt2/build/js-common.js:27:42)
    at Module._compile (module.js:409:26)
    at Object.Module._extensions..js (module.js:416:10)
    at Module.load (module.js:343:32)
    at Function.Module._load (module.js:300:12)
    at Module.require (module.js:353:17)
    at require (internal/module.js:12:17)
    at /Users/JCharnock/Desktop/newatp/pt2/gulpfile.js:31:11
    at Array.forEach (native)
    at Object.<anonymous> (/Users/JCharnock/Desktop/newatp/pt2/gulpfile.js:25:28)

Does anyone have experience with tedious tasks like this? A point in the right direction would be nice.