Updating Ionic 4.0->4.7 Dependency Issues and Build Failure

I found myself needing to update my ionic framework and followed the instructions here
The process went fairly ok but there has been a bunch on apparently unresolvable dependencies coming out of npm:

So, for example, the http@7.2.15 needs a peer, but I have 8.2 installed. The relevant section of my package.json is:

"@angular/forms": "^8.2.1",
"@angular/http": "^7.2.15",
"@angular/platform-browser": "^8.2.1",
"@angular/platform-browser-dynamic": "^8.2.1",

I thought the ^ meant a higher version was required. Surely the Angular team wouldn’t force a dependency like that…(I have tried updating the http, but that is the latest it appears?)

npm i @angular/http@latest

If I install angular core 7.2.15 then that just breaks everything else.

My ionic build breaks with errors which also imply some kind of missing/broken library issue:

I am fairly new to this type of environment coming from the cosseted world of Visual Studio and C#. I have tried a bunch of other things too and seem to be going around in circles now, to the extent Ive considered a new project and moving all the files in kind of thing…

It could of course be that the ‘http’ issue is a red herring and the issue is a wider one. Any ideas where I am missing something? Or where I should look ?