Please help! Recovering a Deleted Site Collection

Hello,

I am in need of assistance. I deleted a site collection from Central Admin but i took its backup before deleting using powershell backup-spsite.

Now when I am trying to restore it to its own new content db, it is taking lots of time. The size of the backup of the site is 103 gigs. I read that it is impossible to restore site collections of more than 100 gigs. 

The content Db on which the site collection used to reside has more site collections than the one I deleted. They are working fine.

Please suggest how I can get back the content db as it is with the deleted site restored somehow. I have the full backup of the content Db though. But I dont have any other farm to test this. 

Can I get the full back up content db somehow replacing the current Content DB? But will that deleted site collection still show as it has no reference now in the config Dbs.

Should I create a new web application and attach the full back up content db to this new web application? But what about the other sites as this would conflict with their site IDs.

Please help. The only hope I have is the content db full backup which has that site.

Sangz