I can establish the VPN tunnel but can only ping the LAN side of the sonicwall at the remote location. The remote sonicwall also does not let internet access to a PC on the LAN side.
So from your office you can ping all the devices on the LAN side of the remote router? (This is what you are wanting!)
But you are stating that any device on the LAN side of the remote router does not have Internet Access! (So the sonicwall router probably has outbound traffic blocked).
There is going to be much more involved to make this work as (I) think you are wanting it to work.
You will have ports that will have to be forwarded on both routers and you will have to setup the endpoint networks so that the router know how to create the BRIDGE.
Example: (Your Office)- this network might be 192.168.1.100-200
And the Remote Network (Will have to be different) but it could be 192.168.2.100-200 and now you program the endpoints in each router and then the VPN will know what network to bridge.
Sonicwall routers are cumbersome to work with you may want to consider a simpler solution, such as E*** very simple to setup and get working.
I have done it both ways and I must say the latter is super easy.
Please this is just my opinion, I'm sure you will find many other solutions here.
Good Luck!