150GB Photoshop file and SSD scratch disk option

Hi all,

First post here so be gentle.

I know this question has been asked a lot but I'm looking for some guidance based on my situation.

I'm working with a PSB file that's 150GB (uncompressed and roughly 208,000 X 208,000 px). This files contains 169 aerial image tiles that are 16,000 X 16,000 px.

I'm in the process of editing the sea so I have a layer with a mask that I'm manually painting in.

This file is located on a server with 10 Gbps Ethernet connection so this not a bottleneck.

Currently the scratch disk is about 800GB.

I'm looking at ways to reducing the loading times of this file.

My PC spec is below, but in a nutshell SSD has OS and Program files and HDD is used solely for scratch disk

I'm looking at getting a 2TB SSD (Samsung 860 Pro) but before I do will this reduce the loading times??

PC Spec:

​Photoshop CS6

Win 10 Pro 64bit

RAM 32GB

GTX 1070 (6GB GRAM)

Intel i7-2600 3.4GHz

256GB SSD (sata 3) (with OS and Program Files) Micron C400-MTFDDAK256MAM

HDD 2TB (1.6TB free) (sata 3) WD RE4 WD2003FYYS 2TB 7200 RPM 64MB Cache

Any help would be much appreciated.